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A  TEXT-BOOK 


PRINCIPLES  AND  PRACTICE 


VETERINARY   MEDICINE 


BY 

DAVID  S.  WHITE,  D.V.M. 

DEAN  OF  THE   COLLEGE  AND  PROFESSOR  OF   VETERINARY  MEDICINE    IN    THE    OHIO 
STATE   UNIVERSITY,  COLUMBUS,  OHIO 


LEA  &  FEBIGER 

PHILADELPHIA  AND  NEW  YORK 


Entered  according  to  the  Act  of  Congress,  in  the  year  1917,  by 

LEA  &   FEBIGER, 
in  the  Office  of  the  Librarian  of  Congress.     All  rights  reserved. 


PEEFACE. 


The  need  of  an  up-to-date,  scientific  text  designed  for 
student  use  has  been  long  felt  by  teachers  of  the  internal 
diseases  of  animals.  The  author  has  personally  experienced 
this  need  as  a  teacher  of  veterinary  students  for  over  twenty 
years.  The  few  books  available  on  the  subject  are  either 
obsolete  or  so  filled  with  errors  that  they  mislead  rather  than 
instruct.  Some  of  the  best  of  them  are  translations  from  the 
German  and  French.  In  too  many  instances  the  translators 
have  been  neither  veterinarians  nor  teachers  of  veterinary 
medicine,  and  too  few  of  them  linguists.  Furthermore,  the 
books  in  this  field  have  not  been  designed  for  undergraduate 
students;  they  are  bulky,  comprehensive  works  of  reference 
of  little  pedagogic  value;  all  of  them  have  been  superseded 
by  newer  editions  in  the  original  tongue. 

Although  this  volume  is  designed  primarily  for  the  student, 
it  will  be  found  valuable  to  the  practitioner,  investigator  or 
intelligent  stockman  who  may  have  need  of  knowledge  of 
the  fmidamental  principles  of  the  practice  of  veterinary 
medicine  presented  in  concise,  clear-cut  and  at  the  same  time 
not  too  dogmatic  form. 

^Miile  the  author  has  many  to  thank  for  assistance  in 
preparing  this  volume,  among  his  fellow  teachers,  investi- 
gators and  practitioners,  he  is  especially  indebted  to  Professor 
D.  H.  Udall,  of  the  New  York  State  Veterinary  College, 
Cornell  University,  who  kindly  read  the  manuscript  and 
offered  many  valuable  suggestions  from  his  rich  experience, 
practically  all  of  which  have  been  incorporated  in  the  book. 
INIessrs.  Lea  &  Febiger  are  also  thanked  for  their  patience, 
courtesy  and  efficient  service  in  making  the  edition  mechanic- 
aUy  good.  D.  S.  W. 

CoLuivtBus,  Ohio,  1917. 


CONTENTS. 


PART  I. 

DISEASES  OF  THE  RESPIRATORY  ORGANS. 

CHAPTER  I. 

Diseases  of  the  Nose  and  Adjacent  Sinuses. 

1.  Rliinitis 17 

Catarrhal 17 

Croupous 20 

Diphtheritic 20 

FolUcular 21 

2.  Epistaxis 22 

3.  Infectious  Rhinitis  of  Swine 23 

4.  Animal  Parasites  in  the   Nose   and   Sinuses   of   the   Head 

(CEstrus  ovis) 24 

5.  Catarrh  of  the  Maxillary  and  Frontal  Sinuses 26 

6.  Catarrh  of  the  Guttural  Pouches 27 

7.  Tympany  of  the  Guttural  Pouch 27 

CHAPTER   II. 

Diseases  of  the  Larynx. 

1.  Laryngitis 28 

Catarrhal 28 

Croupous 30 

Edematous 31 

2.  Paralysis  of  the  Recurrent  Nerve  (Roaring) 32 

3.  Tumors  in  the  Larynx 34 


VI  CONTENTS 

CHAPTER  III. 

Diseases  of  the  Bronchi. 

1.  Catarrhal  Bronchitis 35 

2.  Verminous  Bronchitis 38 

CHAPTER  IV. 

Diseases  of  the  Lungs. 

1.  Congestion  of  the  Lungs 41 

2.  Puhnonarj^  Edema 41 

3.  Bronchopulmonary  Hemorrhage 43 

4.  Pulmonary  Gangrene 44 

5.  Abscess  of  the  Lung 45 

6.  Chronic  Alveolar  Emphysema 46 

7.  Acute  Interstitial  Pulmonary  Emphysema 48 

8.  Pneumonia 49 

Fibrinous 49 

Catarrhal 54 

Foreign-body 57 

Metastatic 58 

Interstitial 59 

9.  Tumors  in  the  Lung 60 

CHAPTER  V. 

Diseases  of  the  Pleura. 

1.  Pleuritis •.      •      ■  Gl 

2.  Hydrothorax 66 

3.  Pneumothorax 66 


PART  II. 
DISEASES  OF  THE  CIRCULATORY  ORGANS. 

CHAPTER  I. 

Diseases  of  the  He.\rt  Sac. 

1.  Pericarditis 69 

2.  Hydropericarilium 71 

3.  Pneumopericardium 72 

4.  Hemopericardium 72 


CONTENTS 


Vll 


CHAPTER  II. 

Diseases  of  the  Heart. 

1.  Nervous  Palpitation  of  the  Heart ^^ 

2.  Slow  Heart  Beat  (Bradycardia) "^ 

3.  Intermittent  Heart  Beat  'J^ 

4.  HjTDertrophy  and  Dilatation  of  the  Heart '5 

5.  Myocarditis 

6.  Endocarditis 

Acute ^^ 

Chronic 

7.  Rupture  of  the  Heart °" 

8.  Aneurysm  of  the  Aorta 

9.  Tumors  in  the  Heart 


PART  III. 

DISEASES  OF  THE  DIGESTIVE  ORGANS. 

CHAPTER   I. 

Diseases  of  the  ;Mouth. 


1.  Stomatitis     . 
Catarrhal 
Vesicular 
Papulous 
Mycotic 


83 
83 
85 
86 
87 


CHAPTER   II. 

Diseases  of  the  Pharynx. 


1.  Pharyngitis  . 

Catarrhal  . 
Suppurative 
Croupous  . 
Diphtheritic 

2.  Paralysis  of  the  Pharynx 

3.  Parasites  in  the  Pharynx 


89 
89 
89 
90 
90 
91 
93 


viii  CONTENTS 

CHAPTER  III. 
Diseases  of  the  Stomach  and  Bowels. 

1.  Gastro-intestinal  Catarrh  of  the  Horse 94 

2.  Bloating  in  the  Ox 97 

3.  Chronic  or  Habitual  Tympany 100 

4.  So-called  Colics  of  the  Horse 101 

Acute  Dilatation  of  the  Stomach 103 

Simple  Impaction  of  the  Intestines 106 

Impaction  of  the  Small  Bowel 106 

Impaction  of  the  Large  Bowel 108 

Impaction  Complicated  with  Abnormal  Displacement  110 

Displacement  of  Large  Bowel 110 

Displacement  of  Small  Bowel Ill 

EmboUc  Colic Ill 

Spasmodic  Cohc 113 

Worm  Colic 113 

5.  Gastro-intestinal  Catarrh  of  the  Ox 114 

6.  Gastro-intestinal  Catarrh  of  Sucklings 118 

7.  Gastro-enteritis '  .      .      .  120 

Simple 121 

Croupous ' 124 

Mycotic 125 

Toxic 128 

8.  Traumatic  Indigestion  of  the  Ox 128 

CHAPTER  IV. 

Animal  Parasites  in  the  Stomach. 

1.  Gastrophilus  (Bots) 132 

2.  Spiroptera 133 

Animal  Parasites  in  the  Intestines. 

1.  Tapeworms  (Cestodes) 133 

2.  Round-worms  (Ascarides) 135 

3.  Palisade-worms  in  the  Intestines 136 

Strongylus  Armatus  in  the  Horse           136 

Strongylus  Tetracanthus  in  the  Horse 137 

Strongylus  Contortus  in  Sheep 138 

Strongylus  Convolutus  in  the  Ox 138 

4.  ffisoi^hagostoma  in  the  Intestines 138 

5.  Echinorhynchus  Gigas  of  Swine 140 

6.  Oxyuris  Curvula 140 

7.  Uncinariasis 141 


CONTENTS  IX 

CHAPTER  V. 

Diseases  of  the  Liver. 

1.  Jaundice l'*^ 

Obstmctive 142 

Malignant 143 

of  Newborn 143 

2.  Hepatitis 144 

Parenchymatous 144 

Chronic  Interstitial 145 

Purulent 146 

3.  The  Liver  Fluke  Disease  (Distomatosis) 147 

4.  Echinococcus  Disease  of  the  Liver 148 

5.  Rupture  of  the  Liver 150 

6.  Necrosis  of  the  Liver 150 

7.  Amyloid  Liver 151 

8.  Carcinoma  of  the  Liver 151 

9.  Gall-stones  (CholeUthiasis) 151 

10.  Parasites  in  the  Liver 151 

CHAPTER  VI. 

Diseases  of  the  Peritoneum. 

1.  Peritonitis 152 

2.  Ascites 155 

3.  Tumors  in  the  Peritoneum 157 

4.  Animal  Parasites  in  the  Peritoneum 157 


PART  IV. 

DISEASES  OF  THE  REPRODUCTIVE  ORGANS. 

1.  Puerperal  Septicemia 159 

2.  Parturient  Paresis  (Milk  Fever) 161 

3.  Abnormahties  in  Sexual  Desire 163 

Nymphomania  (Satyriasis) 163 

Diminished  Sexual  Desire 165 

4.  Sterihty 165 

5.  Impotency 167 


CONTENTS 


PART  V. 

DISEASES  OF  THE  BLOOD  AND  BLOOD-PRODUCING 

ORGANS. 

1.  Anemia 169 

2.  Leukemia 170 

3.  Pseudoleukemia  (Hodgkin's  Disease) 172 

4.  Hydremia 173 

5.  Hemophilia 173 

6.  Scurvy 173 

7.  Infectious  Anemia  of  the  Horse  (Swamp  Fever)  174 

8.  Azoturia 179 


PART  VI. 

DISEASES  OF  METABOLISM. 

CHAPTER  I. 


Diseases  of  Metabolism 
Diabetes       .... 

Diabetes  Insipidus 

Diabetes  Mellitus 

Gout 

Obesity 

Pica  (Licking  Disease) 


5.  Wool  Eating 


185 
185 
186 
186 
186 
187 
188 


CHAPTER  II. 
Diseases  of  Metabolism  Affecting  Phincipally  the  Bones. 

1.  Rachitis  (Rickets) 189 

2.  Osteomalacia 190 


CONTENTS  XI 

PART  VII. 

DISEASES  OF  THE  ORGANS  OF  LOCOMOTION. 

1.  Muscular  Rheumatism 193 

2.  Articular  Rheumatism 194 

3.  Trichinosis 196 

4.  Hog  ^Measles  (Cysticercus  Cellulosse) 197 

5.  Cysticercus  Inermis 198 

6.  Miescher's  Tubules 198 


PART  VIII. 

DISEASES  OF  THE  KIDNEYS. 

1.  Nephritis 199 

Acute  ParenchjTnatous 199 

Chronic  Interstitial 201 

Purulent 202 

Pyelonephritis 203 

Bacterial 203 

Calculous 204 

2.  Uremia 205 

3.  Hyperemia  of  the  Ividneys 206 

4.  Renal  Hemorrhage 206 

5.  Amyloid  Ividney 207 

6.  Kidney  Tumors 207 

7.  Hydronephrosis  (Cystic  Kidney) 207 

8.  Hematuria 208 

9.  Hemoglobinuria 208 

10.  Parasites  in  the  Ividney 208 

Eustrongylus  Gigas 208 


xii  CONTENTS 

PART  IX. 

DISEASES  OF  THE  NERVOUS  SYSTEM. 

CHAPTER  1. 

Diseases  of  the  Brain. 

General 209 

1.  Anemia  of  the  Brain  and  its  Membranes 211 

2.  Congestion  of  the  Brain  and  its  Membranes 212 

3.  Sun-  and  Heatstroke 213 

4.  Traumatic  Injury  and  Concussion  of  the  Brain       ....  214 

5.  Lightning  and  Electric  Stroke 215 

,  G.  Hemorrhage  in  the  Brain  and  its  Membranes  (Apoplexy)       .  216 

7.  Meningo-encephalitis 217 

8.  EncephaUtis 221 

Non-suppurative 221 

Suppurative 223 

9.  Infectious  Mcningo-encephalomyelitis  (Borna  Disease)  225 

10.  Chronic  Hydrocephalus 227 

11.  Brain  Tumors 228 

12.  Gid  of  Sheep 229 

13.  Infectious  Bulbar  Paralysis 231 

CHAPTER  II. 

Diseases  of  the  Spinal  Cord. 

1.  Traumatic  Injury  of  the  Spinal  Cord 234 

2.  Inflammation  of  Coverings  of  the  Cord 236 

3.  Inflammation  of  Substance  of  the  Cord  (Spinal  Myelitis)       .  238 

4.  Compression  of  the  Spinal  Cord 240 

5.  Infectious  Spinal  Paralysis  of  the  Horse 242 

CHAPTER  III. 

Functional  Nervous  Diseases. 

1.  Vertigo 244 

2.  Epilcp.sy 245 

3.  Eclampsia 246 

4.  Catalepsy 246 

5.  Chorea 247 

6.  Spasms  of  the  Diaphragm 247 


CONTENTS  xiii 


PART  X. 

DISEASES  OF  THE  SKIN. 

1.  Eczema 249 

Horse 251 

Ox 251 

Swine 252 

2.  Urticaria 255 

3.  Alopecia 256 

4.  Erythema 257 

5.  Pruritus 257 

6.  Trichorrhexis  Nodosa 258 

7.  Acne        .      .     , 258 

8.  Pemphigus •    .  258 

9.  Mange  (Scabies) 259 

Horse 260 

Sheep 261 

Cattle 264 

Swine 264 

10.  Herpes  (Ringworm) 265 

11.  Favus 267 

12.  Contagious  Pustulous  Dermatitis 267 

13.  Hypoderma  Lineatum  (Warble  Flies) 268 

14.  Lice 269 

15.  Ticks 270 

16.  Screw  Flj^  (Compsomyia  Macellaria) 270 

17.  Chicken  Lice  (Dermonyssus  Avium) 270 

18.  Skin  Filaria 270 

Filaria  Irritans 271 

Filaria  Hemorrhagica 271 

19.  Lip-and-leg  Ulceration  of  Sheep 272 

20.  Bighead  of  Sheep 275 


XIV 


CONTENTS 


PART  XI. 

INFECTIOUS  DISEASES. 

CHAPTER  I. 

Acute  General  Ineectious  Diseases. 

1.  Anthrax 

2.  Malignant  Edema   . 

3.  Black-leg 

4.  Braxy  (Gastroniycosis  Ovis)    .... 

5.  Swine  Erysipelas 

6.  Hemorrhagic  Septicemia 

of  Cattle 

Septic  Pleuropneumonia  of  Calves 
of  Sheep 

7.  Takosis  of  Angora  Goats 

8.  Septicemic  Diseases  of  Newborn  Animals 

Dysentery  of  Sucklings    .... 
Pyosepticemia  of  Sucklings 

9.  Influenza  of  the  Horse 

10.  Infectious  Fibrinous  Pneumonia  of  the  Horst 

11.  Purpura  Hemorrhagica 

12.  Hog  cholera 

13.  Rinderpest    .... 

14.  African  Horse-sickness 

15.  Heartwater  .... 


279 
285 
287 
290 
292 
295 
296 
299 
300 
303 
305 
305 
308 
313 
319 
322 
327 
333 
337 
338 


CHAPTER  II. 

Acute  Exanthematous  Infectious  Diseases. 

1.  Variola  (Pox) 339 

of  Sheep 340 

of  Cow 343 

of  Horse 345 

2.  Foot-and-mouth  Disease 345 

3.  Contagious  Stomatitis  of  the  Horse 352 

4.  Coital  Exanthema 355 


CONTENTS  XV 

CHAPTER  III. 

Acute  Infectious  Diseases  Localized  in  Certain  Organs. 

1.  Strangles 358 

2.  Malignant  Head  Catarrh  of  the  Ox 366 

3.  Necrotic  Stomatitis  of  Calves  (Calf  Diphtheria)     ....  369 

4.  Contagious  Pleuropneumonia  of  Cattle 371 

CHAPTER   IV. 

Infectious  Diseases  Involving  Principally  the  Nervous 
System. 

1.  Tetanus 376 

2.  Rabies 382 

CHAPTER  V. 

Chronic  Infectious  Dise.\ses. 

1.  Tuberculosis 389 

2.  Intestinal  Paratuberculosis  (Johne's  Disease) 410 

3.  Caseous  Lymphadenitis  of  Sheep 412 

4.  Actinomj'cosis 413 

5.  Glanders 417 

6.  Epizootic  Lymphangitis 427 

7.  Ulcerous  Lymphangitis  of  the  Horse 429 

8.  Infectious  Abortion 430 

9.  Infectious  Granular  Vaginitis  of  Cattle 436 

CHAPTER  VI. 

Infectious  Diseases  due  to  Protozoa. 

1.  Piroplasmoses 439 

Piroplasmosis  of  Cattle  (Texas  Fever) 440 

Piroplasmosis  of  European  Cattle    . 446 

East  African  Coast  Fever 448 

Piroplasmosis  of  Horse 449 

Piroplasmosis  of  Sheep 450 

2.  Trypanosomiasis 451 

Dourine 451 

Surra 456 

Nagana 457 

Mai  de  Caderas 458 

3.  Coccidiosis 459 


PART  I. 
DISEASES  OF  THE  RESPIRATORY  ORGANS. 


CHAPTER  I. 

DISEASES  OF  THE  NOSE  AND  ADJACENT 
SINUSES. 

RHINITIS.     NASAL   CATARRH. 

^  Forms. — Depending  upon  the  degree  of  inflammation  the 
following  clinical  forms  of  rhinitis  may  be  distinguished : 
Catarrhal  (acute  and  chronic) . 
Croupous. 
Diphtheritic. 
Follicular. 
Acute  Nasal  Catarrh  (Rhinitis,  Acute  Coryza). — Definition. 
— An  acute  catarrh  of  the  air  passages  of  the  head.    It  may 
occur  as  a  "primary  affection  or  may  be  secondary  to  another 
disease. 

Etiology. — Primary. — It  is  rarely  due  to  the  inhalation  of 
foreign  matter  such  as  dust,  chaff,  grains,  seeds,  etc.  Sponges 
placed  in  the  nostrils  to  prevent  discharge  or  to  reduce  the 
sound  in  roaring  is  an  infrequent  cause.  Irritants,  fumes, 
gases  or  smoke  occasionally  produce  it.  The  common  predis- 
posing cause  is  cold.  Rhinitis  is  most  frequent  during  the 
changeable  weather  of  the  late  fall  and  early  spring.  The 
exciting  cause  is  undoubtedly  infection. 

Secondary. — Nearly  all  of  the  diseases  of  the  respiratory 
tract  are  accompanied  by  rhinitis,  as  are  specific  infectious 
diseases  such  as  strangles,  influenza,  hog  cholera,  glanders. 
2 


IS      DISEASES  OF  THE  NOSE  AND  ADJACENT  SINUSES 

Symptoms. — Tlie  general  condition  of  the  patient  is  usually 
somewhat  disturbed;  it  seems  stupid,  languid,  and  shows 
slight  fever.  The  mucous  membrane  of  the  nose  is  swollen 
and  reddened  and  at  first  drier  than  normal;  later  an  irritant, 
watery  discharge  appears,  which  in  a  day  or  two  becomes 
turbid  and  more  profuse.  In  the  earlier  stages  the  patient 
sneezes  frequently  and  rubs  its  nose  against  objects.  The 
nasal  discharge  dries  and  forms  crusts  at  the  openings  of  the 
nostrils.  In  exceptional  cases  small  round  superficial  erosions 
are  noted  on  the  mucous  membrane,  which  usually  heal  in  a 
few  days.  In  severe  cases  there  is  conjunctivitis  present. 
If  the  larynx  is  involved  there  is  cough;  if  the  pharynx, 
difficulty  in  swallowing.  The  submaxillary  lymph  glands 
in  the  horse  are  slightly  swollen. 

Course. — The  course  is  usually  rapid  and  the  termination 
favorable.  The  condition  in  ordinary  cases  disappears  in 
seven  to  ten  days. 

Treatment. — The  acute  catarrh  seldom  requires  treatment. 
Protecting  the  patient  from  draughts  and  dust  is  all  that  is 
necessary  in  the  average  case.  When,  however,  the  dis- 
charge is  profuse  or  the  patient  shows  fever,  injections  into 
the  nostrils  of  1  to  2  per  cent,  creolin  solution  are  recom- 
mendable.  Inhalations  of  volatile  substances  are  of  value. 
Turpentine  or  benzoin  (1  to  5  per  cent,  in  form  of  steam) 
may  be  tried.  The  crust  on  the  nostrils  may  be  greased 
with  vaseline.  In  man  the  "snuffing"  of  the  fluidextract 
of  hamamelis  every  two  or  three  hours  is  much  employed. 

Chronic  Nasal  Catarrh  (Chronic  Rhinitis,  Ozena). — Chronic 
rhinitis  rarely  develops  from  the  acute.  This  form  is  nearly 
always  secondary  to  some  other  disease  involving  the 
respiratory  tract. 

Etiology. — Bad  teeth  with  filling  of  the  maxillary  or  frontal 
sinuses  with  pus.  It  may  also  accompany  glanders,  tumors 
(polypi)  in  the  nostrils,  animal  parasites  (estrus  larva^  in 
sheep),  chronic  bronchitis,  verminous  l>ronchitis.  In  surgical 
conditions  of  the  head  such  as  necrosis  of  the  turbinated 
bone,  empyema  of  the  sinuses,  etc.,  nasal  catarrh  is  noted. 

Symptoms. — The  principal  symptom  is  nasal  di.scharge, 
which    \aries    gr(>atly    in    (juantity    and    character.     The 


RHINITIS— NASAL  CATARRH  19 

discharge  may  be  quite  copious,  or,  on  the  other  hand,  very 
limited.  As  a  rule,  even  in  a  given  patient,  the  discharge 
is  greater  at  times  (after  a  long  drive  and  when  the  horse 
is  unreined).  In  character  the  discharge  may  be  mucous 
and  viscid,  or  purulent  or  even  blood-streaked  (glanders, 
polypi).  It  is  often  fetid  (teeth,  necrosis  of  turbinated 
bones,  polypi).  The  discharge,  if  limited,  may  dry  at  the 
nostril  openings,  forming  green  to  brownish  crusts  (glanders) 
or  it  may  flow  over  the  upper  lip  depigmenting  the  skin 
over  which  it  passes. 

The  mucous  membrane  assumes  usually  a  leaden  hue, 
although  it  may  appear  brown.  It  is  at  times  swollen,  nodu- 
lar and  pitted  with  round  erosions  or  superficial  ulcers.  The 
swelling  may  interfere  with  breathing,  causing  nasal  dyspnea 
with  sound,  heard  particularly  at  inspiration.  From  a  filling 
and  distention  of  the  turbinal  bones  with  exudate  the 
nasal  septum  may  become  atrophic  and  distorted  through 
pressure  leading  to  partial  occlusion  of  the  nasal  passages. 
.The  submaxillary  lymph  glands  become  indurated  and 
enlarged  but  usually  do  not  adhere  to  the  jaw. 

Diagnosis. — While  the  diagnosis  of  chronic  catarrhal  rhi- 
nitis is  not  difficult,  to  determine  whether  it  is  primary  or 
secondary  often  requires  careful  judgment.  A  thorough 
inspection  of  the  teeth  should  be  made  in  all  cases,  especially 
where  the  discharge  is  fetid  and  unilateral.  Tumors  may 
often  be  felt  with  the  aid  of  a  urinary  horse  catheter  or 
nasal  tube.  A  veterinary  rhinolaryngoscope  (Polonsky- 
Schindelka)  is  useful  in  diagnosis.  If  the  tumor  is  of  con- 
siderable size,  the  air  current  from  the  partially  occluded 
nostril  will  be  less  in  volume.  A  sudden  increase  in  the 
discharge  when  the  head  is  lowered  after  a  drive  speaks  for 
sinus  empyema  or  more  rarely  filling  of  the  guttural  pouches. 
Where  glanders  is  suspected  the  complement-fixation,  mal- 
lein,  agglutination,  precipitin  or  guinea-pig  tests  may  be 
applied.     (See  Glanders.) 

Treatment. — The  treatment  of  chronic  nasal  catarrh  is 
largely  surgical  (trephining  sinuses,  extraction  of  diseased 
teeth,  removal  of  tumor,  etc.).  At  any  rate  it  is  governed 
by  the  primary  disease  which  the  discharge  accompanies. 


20     DISEASES  OF  THE  NOSE  AND  ADJACENT  SINUSES 

TJie  local  treatment  of  the  nose  by  irrigation  or  inlialation 
is  of  little  value  except  in  purely  primary  cases  and  then  it 
must  be  persisted  in  for  weeks  before  permanent  healing  is 
afi'ected.     The  following  combination  may  be  tried: 

1} — TaiiiiMfoiini ,~vj 

Moiitlioli 5.SS 

Alcoliol  (.-)()  por  coiit.) Oj 

A()u:i  tk'st Oss 

M.  I).  S. — A|)pl>-  ats  a  nasal  douche. 

Croupous  Rhinitis.  Definition.  An  inflammation  of  the 
mucous  meml)rane  of  the  nasal  chamber  with  the  formation 
of  pseudomembrane. 

Occurrence. — ^een  in  the  horse  and  ox.  Enzootics  have 
been  noted  in  the  horse. 

Etiology. — It  is  attributed  to  the  inhaling  of  irritant  gases 
and  smoke.  It  is  undoubtedly  due  in  many  cases  to  micro- 
organisms. It  may  follow  suppurative  mastitis  or  metritis 
in  the  mare  and  cow,  and  may  be  secondary  to  malignant 
head  catarrh,  purpura  hemorrhagica,  and  strangles. 

Symptoms. — An  intense  inHannnation  of  the  mucous 
membrane  which  is  deei)  red  and  greatly  swollen.  Patches 
of  gray  or  yellow  red  fibrinous  membranes  form.  The 
false  membrane  sloughs  off  in  a  few  days  leaving  behind 
raw  bleeding  surfaces  which  soon  heal  without  scar.  There 
is  a  free  discharge,  which  may  be  blood-streaked  and  contain- 
ing shreds  of  croupous  membrane.  The  submaxillary 
lymph  glands  and  vessels  are  swollen  and  sensitive.  There 
may  be  nasal  dyspnea.     Temperature  is  elevated. 

Course.     Tsually  ends  in  healing  in  about  one  week. 

Treatment. — It  is  reconuuended  to  touch  the  affected 
])arts  with  hydrogen  dioxide,  full  strength,  to  each  2  ounces 
of  which  has  been  added  a  dram  of  sodium  bicarbonate. 
Do  not  forcibly  remove  the  membranes.  Affected  animals 
should  be  isolated. 

Diphtheritic  Rhinitis. — Definition.  A  necrotic  inflamma- 
tion of  the  mucous  membrane  of  the  nasal  cavities. 

Occurrence. — Seen  in  horses  and  cattle.  It  is  usually 
secondary  to  such  infectious  <liseases  as  acute  glanders, 
purpura  hemorrhagica,  malignant  head  catarrh. 


RHINITIS— NASAL  CATARRH  21 

Etiology. — A  primary  diphtheritic  rliinitis  may  result  from 
the  action  of  any  mechanical,  thermic,  chemical  or  infectious 
irritant  which  is  sufficiently  intensive  to  destroy  the  mucous 
membrane.  In  all  probability  the  necrosis  bacillus  is  a 
factor.  As  noted,  diphtheritic  rhinitis  may  be  secondary  to 
certain  infectious  diseases. 

Symptoms. — The  condition  is  characterized  by  the  appear- 
ance of  yellowish-gray  patches  in  the  mucosa  which  when 
detached  or  sloughed  leave  behind  deep,  dark  red  or  grayish- 
red  ulcers.  The  borders  of  the  ulcers  are  thickened  and 
surrounded  by  a  zone  of  reactive  inflammation.  The 
submaxillary  lymph  glands  are  swollen. 

Diagnosis. — Glanders  should  be  thought  of  and  excluded 
before  a  diagnosis  of  "primary  diphtheritic  rhinitis"  is  made. 
In  purpura  hemorrhagica  the  differential  diagnosis  is  less 
difficult  (petechia,  typical  cutaneous  swellings).  The  eye 
affection  absent  in  primary  nasal  diphtheritis  is  characteristic 
of  malignant  head  catarrh  of  cattle. 

Treatment. — See  Croupous  Rhinitis. 

Follicular  Rhinitis  (Pustulom  Coryza). — Definition. — An 
inflammation  of  the  nasal  mucous  membrane  involving 
particularly  the  mucous  glands  forming  pustules  and  later 
ulcers.  The  sebaceous  glands  of  the  skin  of  the  nostrils 
may  also  become  affected. 

Occmrence. — Peculiar  to  the  horse.  It  may  occur  enzo- 
otically. 

Etiology. — Undoubtedly  microorganisms.  The  Strepto- 
coccus equi  has  been  accused. 

Symptoms. — The  symptoms  are  those  of  a  severe  nasal 
catarrh  with  the  presence  of  numerous  small  nodules  of  the 
size  of  flea-bite  which  appear  on  the  nasal  septum.  By  con- 
fluence large  nodules  may  form.  The  nodules  soon  undergo 
puriform  softening,  become  yellow  and  form  ulcers  which 
heal  in  a  few  days  without  leaving  a  scar.  A  similar  erup- 
tion may  occur  on  the  skin  of  the  nostrils  and  lips.  The 
lymph  vessels  of  the  cheek  are  sometimes  greatly  distended, 
abscesses  forming  rapidly  along  their  course.  The  sub- 
maxillary lymph  glands  become  enlarged  and  sensitive.  A 
follicular   (granular)   conjunctivitis  may  be  present. 


22     DISEASES  OF  THE  NOSE  AND  ADJACENT  SINUSES 

Diagnosis.  Tlu'  disease  might  be  confused  with  glanders. 
The  benign  course  and  rapid,  clean  healing  of  the  ulcers 
make  tiie  difl'erentiation   not  difficult. 

Treatment. — Treat  as  in  catarrhal  rhinitis.  I'lcers  may 
be  dressed  with  any  strew-powder  (iodoform,  compound  alum 
powder,  etc.).  The  swollen  lymph  vessels  may  be  smeared 
with   gray   mercurial   ointment. 

EPISTAXIS. 

Definition. — Bleeding  from  the  nose. 

Etiology. — {(I)  Ilcrcdify. — In  some  families  of  horses  it 
is  an  inherited  predisi)osition.  In  such  cases  (hemoi)hilia?) 
epistaxis  occurs  without  apparent  cause.  It  may  follow 
overexertion  in  race  horses  (predisposition?), 

(b)  Truuinaiism. — Epistaxis  commonly  results  from  direct 
or  indirect  traumatism.  Passing  objects  up  into  the  nostrils 
(sponges,  straw  whisps,  nasal  tubes,  etc.)  is  often  followed 
by  bleeding.  In  forcibly  ejecting  dust  and  foreign  matter 
from  the  nose  horses  sometimes  induce  hemorrhage.  I^^rac- 
tures  of  the  jaw  (maxillary  process)  and  of  the  base  of  the 
cranium  may  be  followed  by  nosebleed. 

{(■)  Heart  and  Luiuj  DiseaM's. — In  animals  suti'ering  from 
chronic  heart  and  lung  diseases  this  diathesis  is  present. 

{(1)  Pressure  on  ,1  iKjuJars. — Contiiuied  pressure  on  the 
jugulars  may  be  a  cause. 

{e)  Infectiovs  Diseases. — In  many  of  the  acute  infectious 
diseases  it  is  a  symptom  (anthrax,  purpura  hemorrhagica, 
glanders,  septicemia),  and  in  such  blood  diseases  as  leukemia, 
l)seudoleukemia,  anemia,  etc. 

(/)  Tumors. — Tumors  in  the  nasal  chambers  (angiomas, 
sarcomas)  induce  bleeding. 

Symptoms. — The  blood  either  drops  from  the  nostril  or 
flows  in  a  thin  stream.  It  is  not  foamy  and  not  attended  by 
dy.spnea.  There  are  no  general  symptoms  unless  the  hemor- 
rhage is  copious  or  recurs  frequently  where  it  causes  general 
anemia  (pale  mucous  membranes,  small  rapid  pulse,  anxious 
expression,  dyspnea).  Kepeated  hemorrhages  at  fre(|uent 
intervals  ma\'  become  fatal  in  six  to  nine  da\  s. 


INFECTIOUS  RHINITIS  OF  SWINE  23 

Diagnosis. — It  is  usually  not  difficult  to  determine  the 
origin  of  the  hemorrhage  but  to  find  the  cause  may  require 
a  most  careful  examination  of  the  patient.  Pulmonary  hem- 
orrhages are  characterized  by  a  bright  red,  foamy  bilateral 
nasal  discharge  accompanied  by  cough,  dyspnea,  and  weak 
pulse.  On  auscultation  of  the  chest,  rales  are  heard.  How- 
ever, if  from  a  nasal  hemorrhage  some  of  the  blood  is  aspirated 
into  the  liuigs,  symptoms  of  pulmonary  hemorrhage  may  be 
simulated,  complicating  the  diagnosis.  In  gastric  hemor- 
rhage the  blood  is  more  or  less  clotted,  brown  in  color,  of 
acid  reaction,  and  mixed  with  food  particles.  In  the  horse 
and  ox  it  may  be  ejected  thrbugh  the  nostrils,  but  in  the 
hog  and  in  carnivora  it  is  vomited  through  the  mouth. 

Treatment. — The  patient  should  be  kept  in  a  cool  quiet 
place.  If  the  hemorrhage  is  severe  enough  to  warrant  it, 
inject  into  the  nostrils  adrenalin  in  salt  solution  (1  to  5000). 
Tincture  of  ferric  chlorid  is  serviceable.  If  injections  do 
not  suffice,  tampon  the  nostril  or  nostrils  with  gauze  soaked 
in  adrenalin.  In  the  horse  and  ox  tracheotomy  should 
be  performed  before  plugging  both  nostrils.  Intravenous 
injection  of  a  2  per  cent,  gelatin  solution  in  salt  solution  has 
been  effective.  In  slight  hemorrhages  turpentine  may  be 
given  internally.  When  bleeding  comes  from  an  angioma 
in  the  septum,  touching  with  lunar  caustic  may  stop  it. 

INFECTIOUS    RHINITIS    OF    SWINE. 

Definition. — An  infectious  disease  of  the  nose,  ethmoid  and 
brain  of  young  pigs  due  to  the  Pseudomonas  pyocyaneus, 
the  microorganism  of  blue  pus. 

Natural  Infection. — Takes  place  through  the  nose  from  the 
pigs  rooting  in  infected  straw,  manure,  etc. 

Symptoms. — The  prodromal  symptoms  are  those  of  fever 
(loss  of  appetite,  languor).  Nasal  symptoms  soon  appear. 
The  patient  passes  air  rapidly  in  and  out  of  the  nostrils, 
producing  a  snorting  or  sniffling  sound;  the  snout  is  fre- 
quently rubbed  against  objects.  There  is  bloody  nasal 
discharge  mixed  with  pus.  The  snout  becomes  edematous 
and  swollen.     In  severe  cases  on  about  the  third  dav  of  the 


24      DISEASES  OF   THE  NOSE  AXD  ADJACENT  SINUSES 

attack  symptoms  of  cerebral  excitement  occur,  the  pig 
showing  ral)iforni  symptoms  and  convulsions. 

Course. — The  usual  course  of  the  disease  is  from  two 
to  se\'en  days.  Sometimes  it  assumes  a  chronic  form. 
Kecovery  is  rare. 

Diagnosis. — The  high  fever,  rhinitis  with  pronounced  brain 
symptoms  and  without  deformity  (bulging)  of  the  facial 
bones  are  characteristic.  It  is  distinguished  from  rachitis 
by  the  absence  of  fever,  facial  deformity  and  dropping  of  the 
hard  palate  in  tliis  disease.  Actinomycosis  and  tubercu- 
losis may  cause  thickening  of  the  snout  and  nasal  discharge 
in  swine.  The  course,  however,  is  chronic  and  there  is  no 
nasal  hemorrhage.  In  doubtful  cases  a  microscopic  and 
bacteriological  examination  of  the  discharge  may  be  made. 
It  might  be  confused  with  hyperacute  cases  of  hog  cholera, 
in  which  at  times  epistaxis  and  brain  symptoms  occur. 
The  epizootic  character  of  this  disease,  the  bowel  lesions 
on  postmortem  and  the  absence  of  rhinitis  make  the  differ- 
entiation usually  easy. 

Treatment. Of  little  avail.  In  valuable  pigs  irrigating  the 
nostrils  with  bichlorid  solution  (1  to  1000)  may  be  tried. 
It  is  usually  better  to  slaughter  the  affected  animals  and 
thoroughly  disinfect  the  pens.  As  the  disease  is  spread  by 
the  infected  nasal  discharge,  a  separation  of  the  healthy  from 
the  sick  is  indicated. 

ANIMAL   PARASITES   IN   THE    NOSE   AND    SINUSES 
OF    THE    HEAD. 

Grub  in  the  Head  of  Sheep.    GCstrus  Ovis. 

Definition. ^A  catarrli  of  the  nasal  chambers  and  sinuses 
of  the  head  due  to  the  larva'  of  the  bot  Hy,  G^^strus  ovis. 

Occurrence. — Found  in  all  countries  where  the  sheep  bot 
exists.  Australia  is  said  to  be  exempt.  Few  American 
shee])  are  free  from  grub. 

Etiology. — 1'he  shee})  are  usually  attacked  by  the  parent 
bot  fly  during  the  hot  season.  It  is  said  that  the  fly  may 
even  be  active  in  winter  in  warm,  sunny  sheej)  folds. 


ANIMAL  PARASITES  IN  NOSE  AND  SINUSES  OF  HEAD   25 

Life  History.— The  larvje  are  deposited  by  the  swift-flying 
female  bot  on  the  margin  of  the  sheep's  nostrils,  from  whence 
they  crawl  up  into  the  nasal  chambers,  cavities  of  the  turbi- 
nal  bones,  ethmoid  cells  and  even  horn  cores.  It  is  possible 
that  the  brain  is  invaded  in  some  cases.  They  attach  them- 
selves to  the  mucous  membrane  to  feed  and  develop.  They 
usually  remain  in  the  sheep  about  ten  months,  or  until  the 
following  spring  when  they  leave  via  nasal  passages  and 
reach  the  ground.  In  the  soil  in  one  or  two  days  they  pass 
into  the  chrysalis  form  out  of  which  emerges  in  six  to  eight 
weeks  the  mature  bot  fly.  The  impregnated  female  bot 
seeks  sheep  herds.  She  usually  hides  in  cracks  and  crevices 
in  the  sheep  barn  or  on  shrubbery  or  underbrush  near  the 
sheep  pasture.  Sheep  try  to  avoid  the  attacks  of  the  fly 
by  running  away  from  it  with  their  noses  held  close  to  the 
ground  or  by  grouping  themselves  in  a  great  mass,  their 
heads  toward  the  centre.  If  the  fly  touches  the  nostril,  the 
sheep  will  snort,  stamp  its  feet  and  rub  its  nose  on  the  fore- 
legs or  ground.  They  often  seek  dusty  places  in  the  pasture 
to  avoid  the  fly.  Once  the  larvse  have  gotten  into  the  head, 
however,  the  sheep  become  quiet  and  remain  so  until  the 
emigration  of  the  parasite  begins. 

Symptoms. — If  only  one  or  two  grubs  are  present,  beyond  a 
slight  nasal  discharge,  the  sheep  may  show  no  symptoms. 
When  large  numbers  are  in  the  head,  however,  the  patients 
show  profuse  mucopurulent  or  even  bloody  nasal  discharge, 
sneezing,  snorting,  sniffling,  shaking  the  head  and  rubbing 
the  nose  against  objects.  In  severe  cases  symptoms  of 
vertigo  occur,  the  patient  staggering,  reeling,  and  falling 
to  the  ground.  Sometimes  fatal  convulsions  are  noted. 
Conjunctivitis  may  be  present.  x\s  a  rule,  however,  in 
about  ten  days  after  the  first  signs  appear,  and  the  larvje 
are  expelled,  the  symptoms  subside. 

Diagnosis. — Grub-in-the-head  may  be  confused  with  sturdy 
or  gid  (Coenurus  cerebralis).  However,  in  sturdy  the  older 
sheep  are  attacked,  there  are  no  nasal  symptoms  and  the 
forced  movements  of  the  patient  are  more  pronounced.  Gid 
is  furthermore  as  yet  an  uncommon  disease  in  the  United 
States.  In  doubtful  cases  a  postmortem  or  the  micro- 
scopic examination  of  the  discharge  must  decide. 


2()      DISEASES  OF  THE   NOSE  AND  ADJACENT  SINUSES 

From  verminous  bronchitis  it  may  he  (Hstinguished 
by  the  absence  of  the  cough  and  rales  on  auscultation  so 
characteristic  of  bronchitis. 

Treatment. — Xerx  unsatisfactory.  Trephining  the  sinuses 
and  removing  the  larvae  with  forceps  is  only  practicable  in 
isolated  cases  and  among  valuable  sheep.  Nasal  douches 
do  not  reach  the  larvae  in  the  sinuses.  In  severe  cases 
slaughter  is  the  most  economical  disposition. 

Prevention. — It  is  recommended  to  place  in  the  pa.sture 
field  a  log  in  which  a  number  of  2-inch  augur  holes  have 
been  bored.  Salt  is  put  in  the  bottom  of  each  hole  and 
around  the  margin  tar.  When  the  sheep  attempt  to  get  the 
salt  the  nostril  becomes  tar-smeared,  which  partially,  at 
least,  protects  against  the  bot  fly.  Allowing  the  sheep 
constant  access  to  lime  is  of  some  value.  Plowing  a  few 
furrows  in  the  pasture  serves  to  furnish  dust  in  which  the 
sheep  may  burrow  their  noses  to  avoid  the  fly. 

CATARRH   OF   THE  MAXILLARY   AND   FRONTAL 
SINUSES. 

Definition. — A  collection  of  mucopurulent  exudate  in  the 
sinuses  of  the  head. 

Occurrence. — Commonest  in  the  horse,  but  is  seen  in  the 
ox.     In  cattle  the  frontal  sinuses  are  usually  involved. 

Etiology. — Most  frc(iucntly  due  to  diseases  of  the  teeth 
(dental  caries;  alveolar  periostitis).  In  cattle  it  may  follow 
dehorning.  Certain  infectious  diseases  such  as  glanders, 
malignant  head  catarrh,  etc.,  may  induce  it. 

Symptoms. — Xasal  discharge  which  is  often  unilateral.  It 
may  be  intermittent,  coj)ious  or  limited,  and  sometimes 
fetid.  In  some  cases  the  bone  covering  the  sinu.ses  is  atro- 
phied and  bulged  outward,  distorting  the  face.  There  may 
be  conjunctivitis  and  i)artial  occlusion  of  the  lacrimonasal 
duct.  Swelling  of  submaxillary  lynii)h  gland  of  the  affected 
side  is  usually  noted. 

Diagnosis.— AVith  a  drill  or  gimlet  bore  into  the  su.spected 
sinus. 

Treatment. — Surgical. 


TYMPAXY  OF  GUTTURAL  POUCH  2i 

CATARRH    OF    THE    GUTTURAL   POUCHES. 

Definition.— An  accumulation  of  exudate  in  the  guttural 
pouches.  In  some  cases  the  pouch  is  filled  with  solid,  cheesy 
bodies,  each  of  about  the  size  of  a  bean  (dried  pus).  Disten- 
tion of  the  pouch  with  gas  may  result  from  a  decomposition 
of  the  exudate. 

Etiology. — Rarely  foreign  bodies;  spread  of  inflammation 
from  neighboring  organs;  infection  (glanders). 

Symptoms. — Similar  to  those"  of  chronic  nasal  catarrh. 
Swallowing  and  breathing  may  be  interfered  with.  Swelling 
in  the  subparotid  region. 

Treatment. — Surgical. 

TYMPANY    OF    GUTTURAL   POUCH. 

Definition. — A  distention  of  the  pouch  with  air  or  gas. 

Occurrence. — Colts  born  with  it.  In  older  horses  may  also 
occur  secondary  to  catarrh  of  pouches. 

Etiology.— A  congenital  deformity  of  the  tube  or  its  valve. 
Secondary  to  catarrh  of  the  pouches. 

Symptoms.— An  elastic,  pneumatic  swelling  in  the  parotid 
region.  May  induce  dyspnea,  roaring,  and  dysphagia. 
Nasal  discharge  may  fail. 

Treatment. — Surgical.     Rarely  successful. 


CHAPTER  II. 
DISEASES  OF  THE  LARYNX. 

LARYNGITIS. 

Clinically  laryngitis  may  be  classified  into: 
Catarrhal  (acute  and  chronic). 
Croupous. 
Edematous. 

Catarrhal  Laryngitis. — Definition. — A  superficial  inflamma- 
tion of  the  mucosa  of  the  larynx.  Usually  the  upper  part 
of  the  trachea  and  often  the  pharynx  are  also  invoh'ed 
(laryngotracheitis,  laryngopharyngitis). 

Occurrence. — Catarrhal  laryngitis  is  one  of  the  commonest 
diseases  of  horses  and  cattle.  It  frequently  assumes  an 
enzootic  form,  being  very  prevalent  during  the  changeable 
weather  of  si)ring  and  fall.  The  disease  may  be  primary  or 
secondary. 

Etiology. — The  causes  of  primary  laryngitis  are:  refrigera- 
tion, inhalation  of  irritant  dust,  gases,  ingestion  of  ferment- 
ing foods  (brewer's  grains,  distillery  sloi)s,  potato  residue), 
continued  bellowing  of  cattle,  throat  latch  of  bridle  too 
tight,  and  primary  infections. 

Secondary  laryngitis  accompanies  many  of  the  infectious 
diseases,  especially  influenza  and  strangles  of  the  horse, 
tuberculosis  of  the  ox,  cholera  of  swine,  and  verminous 
bronchitis  of  sheep.  A  spread  of  inflanunation  from  neigh- 
boring organs  (pharynx,  trachea)  may  induce  laryngitis. 
The  causes  of  chronic  catarrhal  laryngitis  are  the  same 
as  those  of  the  acute  form,  the  irritant  acting  mildly  but 
repeatedly  or  persistently. 

Symptoms. — A  dominant  symptom  of  laryngitis  is  a  dry, 
harsh  cough  which  the  patient  seeks  to  suppress.  It  is 
especially  noticeable  when  the  animal  is  brought  out  into 


LARYNGITIS  29 

cold  air  or  given  a  cold  drink  of  water.  Excitement  also 
induces  cough.  The  larynx  is  sensitive  to  pressure  which 
may  bring  about  a  paroxysm  of  coughing.  In  some  patients 
hoarseness  is  evident.  On  auscultation  over  the  larynx 
stenotic,  rough,  sometimes  whistling  tones  are  heard  which 
tend  to  diminish  in  intensity  toward  the  chest.  Nasal 
discharge  is  usually  present.  If  the  pharynx  is  also  involved 
(larvngopharyngitis)  there  will  be  dysphagia.  The  lymph 
glands  of  the  submaxillary  region  are  swollen  and  sensitive. 
Except  in  secondary  laryngitis  the  pulse  and  temperature 
remain  about  normal.  Dyspnea  is  only  present  when  there 
is  marked  swelling  of  the  mucosa. 

Diagnosis.— The  diagnosis  depends  upon  the  presence  ot 
cough,  sensitiveness  of  the  larynx,  mild  fever,  and  the 
negative  evidence  adduced  from  a  thorough  examination 
of  the  lungs.  Secondary  laryngitis  may  be  distinguished 
from  primary  forms  by  the  high  temperature,  general  depres- 
sion of  the  patient  and  symptoms  of  the  primary  disease. 

Course.— In  acute,  catarrhal  laryngitis  the  course  is  usually 
six  to  ten  days  ending  in  complete  recovery.  Neglected  cases 
may  become  chronic  and  last  for  months  causing  persistent, 
obstinate  cough,  but  usually  no  further  symptoms. 

Treatment.— The  patient  should  be  allowed  fresh  air  (not 
too  cold)  free  from  draughts,  dust,  and  stable  gases.  If  the 
weather  permits,  exercise  in  the  open  should  be  allowed. 
In  mild  attacks  horses  may  be  employed  at  light  work 
provided  thev  are  protected  against  high  wind  or  drenching 
rains.  The  food  should  be  laxative  (roots,  grass)  and  free 
from  dust.  . 

Priessnitz  applications  to  the  throat  are  valuable.  During 
the  early  stages  inhalations  of  steam  (camphor,  turpentine, 
creolin) '  are  of  service.  On  the  other  hand,  in  the  later 
stages  when  the  mucosa  is  covered  with  tough  mucus,  such 
solvent  agents  as  common  salt  solution  or  bicarbonate  ot 
sodium  (1  to  3  per  cent.)  are  effectual.  If  the  exudate  is 
abundant  and  fluid,  astringents  (alum  1  to  25  per  cent., 
nitrate  of  silver  0.5  to  1  per  cent.)  are  indicated.  In  horses 
these  remedies  may  be  injected  through  a  small  catheter 
inserted    in    the   nose.     Internally   heroin   in  the  form   of 


30  DISEASES  OF  THE  LARYNX 

j^lyc'oheroin  (1-  to  2-()z.  doses  three  times  daily)  is  of  service. 
Very  popular  is  "  Equine  Cough  Syrup"  (Parke,  Davis  &  Co.). 
The  following  prescription  is  effectual  in  horse  practice: 

I^ — Hcroini  hydrochloridi Kr.  viij 

Potassii  aectatis 5'ij 

Tiiict..  aconiti 3iv 

Spirit  us  setheris  nitrosi  S'v 

Syrupi (|.  s.     Oj 

M.     Sig. — An  ounce  every  two  hours  for  cough  and  fever  in  horse. 

For  expectorant  powders  which  may  be  used  see  Bronchitis. 

Chronic  laryngitis  in  large  animals  may  be  treated  by 
intralaryngeal  injections  through  the  cricotracheal  liga- 
ment, using  a  special  curved  hollow  needle.  Usually  1  oz. 
of  the  following  solutions  is  used :  0.5  per  cent,  acetate  of 
lead,  0.1  per  cent,  nitrate  of  silver,  0.5  per  cent.  alum.  The 
bowels  should  be  kept  open  by  administering  Carlsbad 
salts. 

Obviously  in  secondary  laryngitis  accompanying  con- 
tagious diseases  the  separation  of  the  sick  from  the  healthy, 
and  a  thorough  disinfection  of  the  premises  should  be 
enforced. 

Croupous  Laryngitis  {Mouhranoits  L(iryn(/iti.s). — Defini- 
tion.— A  form  of  laryngitis  characterized  by  the  dcA'elopment 
of  a  fibrinous  pseudomembrane  on  the  laryngeal  mucosa. 
Usually  the  i)harynx  and  trachea  are  also  involved. 

Occurrence. — "^riiis  is  a  rather  rare  disease  occurring 
primarily  in  sheep  and  cattle  and  more  rarely  in  horses  and 
swine. 

Etiology. — Croupous  laryngitis  may  be  either  primary  or 
secondary.  Primary  cases  result  from  the  inhalation  of 
irritant  gases,  smoke,  heated  air,  etc.  Occasionally  following 
a  stable  fire  or  the  use  of  strong  irritant  disinfectants  cases 
occur.  Sheep  driven  through  deep  dust  to  increase  the 
weight  of  the  wool  are  sometimes  attacked.  The  exciting 
cause,  however,  is  evidently  infection  with  probably  the 
necrosis  bacillus  or  streptococci. 

Secondarily,  croui)()Us  laryngitis  is  a  symptom  of  malig- 
nant head  catarrh,  necrotic  stomatitis  of  calves,  purpura, 
glanders  (acute),  rinderpest,  etc. 


LARYNGITIS  31 

Symptoms. — The  disease  begins  as  an  acute  catarrh  of  the 
larynx  that  develops  rapidly  producing  severe  dyspnea 
which  reaches  a  high  degree  in  one  or  two  days.  The  tem- 
perature is  high,  chills  occur,  and  the  patient  is  prostrated. 
There  is  loss  of  appetite.  A  prominent  clinical  symptom 
is  dyspnea  associated  with  loud  laryngeal  tones,  swelling, 
and  sensitiveness  in  the  region  of  the  throat.  Slight  press- 
ure produces  spasmodic  cough  which  may  lead  to  apnea. 
During  the  act  of  coughing  the  patient  ejects  at  first  quan- 
tities of  mucus  and  pus  through  the  nostril.  Later  croupous 
masses  may  be  coughed  up  which  usually  temporarily  or 
permanently  improves  the  condition.  The  lymph  glands 
of  the  submaxillary  region  are  swollen  and  tender.  In  some 
instances  the  feces  are  covered  with  flakes  of  mucus  or  fibrin. 

Course. — Very  acute.  In  fatal  cases  death  usually  results 
in  three  days  from  asphyxia,  or  the  patient  may  die  in  ten 
days. 

The  prognosis  is  fair.  About  50  per  cent,  of  the  cases 
reco\er. 

Diagnosis. — The  high  fever,  peculiar  hoarse  cough,  stenotic 
(roaring)  inspiratory  tone  and  the  coughing  up  of  fibrinous 
masses  are  the  most  important  diagnostic  points.  One 
should  be  on  the  lookout  for  foreign  bodies,  edema  of  the 
glottis,  and  tumors  in  or  near  the  larynx  from  the  stand- 
point of  difi'erential  diagnosis. 

Treatment. — The  inhalation  of  alkalies  such  as  lime  water 
repeated  every  two  hours  and  infrictions  over  the  throat  are 
recommended.  The  principal  indication,  however,  is  an 
early  tracheotomy.     Alcohol  per  rectum  may  also  be  used. 

Edematous  Laryngitis  {Edema  of  the  Glottis). — Definition. — 
By  edema  of  the  glottis  we  understand  a  serous  infiltration 
of  the  submucous  connective  tissue  of  the  upper  part  of 
the  larynx  (ventral  surface  of  the  epiglottis,  epiglottic-ary- 
tenoid folds  and  the  walls  of  the  saccules  of  the  larynx). 
The  edematous  swelling  produces  marked  stenosis  of  the 
larynx  with  resulting  severe  dyspnea.  According  to  cause 
we  may  distinguish : 

(a)  An  inflammatory  edema. 
(6)  A  non-inflammatory  edema. 


32  DISEASES  OF  THE  LARYNX 

The  iiiHaniiiiatory  edema  may  be  primary  due  to  the 
causes  of  inflammation,  or  secondary  and  associated  with 
purpura,  jihinders,  pyemia  or  pneumonia. 

The  non-inflammatory  edema  is  the  result  of  the  venous 
congestion  of  the  hirynx  due  to  chronic  heart  diseases, 
traumatic  pericarditis  of  the  ox,  and  compressions  of  the 
juguhirs  in  horses  from  ill-fitting  collars. 

Symptoms. — The  symptoms  in  both  of  these  conditions 
are  much  the  same  excej)t  that  the  non-inflammatory  form 
usually  develops  more  slowly.  Clinically,  edema  of  the 
glottis  is  manifested  by  a  severe  inspiratory  dyspnea  of  sud- 
den development.  The  patient  shows  marked  "air  hunger" 
by  standing  with  head  held  extended,  anxious  expression, 
general  outbreak  of  sweat,  forefeet  apart,  and  rarely  saliva 
and  food  dropping  from  the  nose  and  mouth.  The  dyspnea 
is  attended  by  a  loud  roaring  sound  f)ccurring  at  each  inspira- 
tion. The  mucous  membranes  become  bluish  and  the  pulse 
and  respiration  increased.  Sometimes  paroxysms  of  cough 
are  present.  Unless  relieved  the  patient  may  die  in  a  few 
hours.     Some  cases  recover  spontaneously,  however. 

Prognosis. — The  ])rognosis  is  not  faNorable  unless  treat- 
ment is  administered  early. 

Treatment. — The  treatment  consists  in  performing  trache- 
otomy, and  in  cases  due  to  heart  diseases,  etc.,  blood-letting 
may  be  practised.  In  milder  cases  Lloyd's  lobelia  (20  c.c. 
subcutaneously)  has  given  good  results. 

PARALYSIS  OF  THE  RECURRENT  NERVE. 

HoARIXG. 

Definition. — lioaring  may  be  defined  as  an  unsoundness 
characterized  by  dyspnea  (always  inspiratory),  and  cough 
due  to  paralysis  of  the  left  recurrent  nerve.  The  condi- 
tion is  always  chronic  and  can  be  relieved  in  about  <S0  ])er 
cent,  of  the  cases  by  operation. 

Etiology. — From  a  practical  standpoint  recurrent  paralysis 
nuiy  l)e  classified  as  primary  or  secondary. 

The  causes  of  the  primary  paralysis  are  not  understood. 
It  seems  as  if  heredity  played  a  part  in  that  stallions  and 


PARALy;SIS  OF   THE  RECURRENT  NERVE  33 

mares  which  are  roarers  transmit  the  tendency  to  their 
progeny.  The  condition  usually  does  not  develop  until 
about  the  fourth  to  sixth  year.  As  a  rule  only  the  left 
side  is  affected,  although  exceptions  are  noted. 

Secondarily,  recurrent  paralysis  may  be  a  sequela  to 
influenza,  strangles,  and  dourine,  or  it  may  follow  an  attack 
of  forage  poisoning  or  poisoning  with  lead  or,  more  rarely, 
goitre  or  direct  injury  to  the  nerve  itself. 

Symptoms. — Usually  in  primary  cases  the  disease  comes 
on  gradually.  It  is  at  first  but  slightly  developed,  the 
patient  only  emitting  a  noisy  sound  when  exercising.  As  a 
rule,  if  the  horse  be  at  rest  no  signs  of  the  disorder  are 
noticed.  If  the  upper  rings  of  the  trachea  be  pinched  a 
prolonged  hoarse  throat  cough  is  heard.  In  many  instances, 
however,  cough  is  absent.  It  is  sometimes  possible  to 
cause  the  patient  to  emit  a  peculiar  grunt  if  it  is  struck  a 
sudden,  unexpected  blow  with  the  hand  on  the  side  of  the 
chest.  The  principal  symptom  of  roaring,  however,  is  the 
audible  laryngeal  sound  emitted  during  and  increased  by 
exercise.  The  quality  of  the  sound  suffers  many  modifica- 
tions from  a  whistle  to  a  pronounced  roar,  which  in  some 
animals  can  be  heard  a  distance  of  several  yards.  Pressing 
the  left  or  right  ar\i:enoid  cartilage  with  the  index  finger 
increases  the  sound.  In  well-developed  cases  sufficient 
exercise  can  produce  apnea.  By  compressing  the  nostrils 
to  one-half  their  normal  dilatation  the  sound  is  temporarily 
diminished.  Generally  the  roaring  sound  ceases  after  five 
to  ten  minutes'  rest  but  returns  again  during  exercise.  In 
mild  cases  it  stops  as  soon  as  the  animal  is  "pulled  up" 
after  a  hard  gallop.  In  bad  cases  the  dyspnea  is  both  ex- 
and  inspiratory. 

Diagnosis. — The  examination  of  the  patient  should  be 
made  under  motion.  The  horse  may  be  ridden,  galloped  on 
a  lunging  line  or  led  behind  a  buggy.  In  some  mild  cases 
the  animal  may  suppress  the  sound  by  extending  the  head. 
To  avoid  this  the  head  should  be  drawn  in,  the  neck  held 
well  arched.  The  use  of  the  laryngoscope  which  shows  the 
asymmetry  of  action  of  the  arytenoids  is  of  great  value  in 
diagnosis. 
3 


34  DISEASES  OF  THE  LARYNX 

Course. — Tlie  course  of  primary  roaring  is  clironic.  Duo  to 
the  increasing  atrophy  of  the  crico-arytenoid  muscles  on  the 
left  side  the  condition  grows  worse  with  time.  INIany  roaring 
horses  may  be  used  for  light,  sh)W  work  while  others  are 
practically  worthless  for  service.  This  depends  largely  upon 
how  deep  into  the  lumen  the  arytenoid  cartilage  sinks  and 
whether  or  not  the  hypertrophic  fellow  muscles  of  the 
opposite  side  can  act  as  compensators  for  the  diseased  ones 
of  the  left. 

Some  cases  of  secondary  roaring  (forage  poisoning, 
strangles)  recover  spontaneously  in  four  to  six  months. 

Prognosis. — About  80  per  cent,  can  be  either  relieved  or 
cured   by   surgical   interference. 

Treatment. — The  most  successful  treatment  consists  in 
the  removal  of  the  laryngeal  saccule  of  the  affected  side. 

TUMORS   IN    THE   LARYNX. 

Occurrence. — In  domestic  animals  tumors  in  the  larynx 
are  not  common.  Occasionally  we  run  across  them  in 
horses  and  cattle.  The  commonest  ones  are  cysts  which 
develop  on  the  anterior  surface  of  the  epiglottis  or  exception- 
ally below  the  cricoid  cartilage.  They  attain  the  size  of  a 
hen's  egg  and  are  filled  with  a  slimy  fluid.  Fibromas, 
lij)omas,  melanomas,  and  carcinomas  are  rare.  Chondromas 
sometimes  occur  in  horses  involving  the  arytenoid  and 
cricoid  cartilages  and  i)roduce  symptoms  of  roaring.  Poly- 
poid tumors  occur  associated  with  chronic  laryngitis.  In 
cattle  tubercular  and  actinomycotic  growths  are  not 
uncommon. 

Symptoms.  -  Tumors  of  the  larynx  produce  (lysj)nea  and 
dysphagia.  The  dyspnea  resembles  that  noted  in  roaring. 
It  is,  however,  not  infrequently  intermittent  and  occasionally 
tends  to  decrease  rather  than  increase  on  exercise.  There 
is  sometimes  blood-streaked  nasal  discharge.  A  diagnosis 
can  usually  be  arrived  at  by  palpation  through  the  mouth, 
the  use  of  the  laryngoscope  or  an  -exploratory  opening  of 
the  larynx.  The  treatment  is  surgical  and  consists  in  the 
extirpation  of  the  tumor.     (See  Surgery.) 


CHAPTER  III. 
DISEASES  OF  THE  BRONCHI. 

CATARRHAL   BRONCHITIS. 

Definition. — By  the  term  bronchitis  an  inflammation  of  the 
larger  bronchi  is  understood  (macrobronchitis).  Bronchio- 
litis (microbronchitis)  is  used  to  express  an  inflammation  of 
the  capillary  bronchi  (bronchitis  capillaris). 

Occurrence. — Bronchitis  occurs  either  as  a  primary  or 
secondary  disease.  It  is  very  common  among  all  domesti- 
cated animals  particularly  during  the  spring  and  fall  when 
it  may  become  enzootic  among  horses  and  cattle.  It  may 
occur  alone  but  is  usually  associated  with  tracheitis  and 
laryngitis  (catarrh  of  the  air  passages),  or  on  the  other  hand, 
may  attend  pneumonia  (bronchopneumonia). 

Forms. — Several  different  forms  of  catarrhal  bronchitis 
are  recognized.  When  the  exudate  is  fluid  and  abundant, 
moist  bronchitis  or  blenorrhea  of  the  bronchi  is  spoken 
of.  If  the  exudate  is  rather  limited  and  not  so  fluid  a  dry 
bronchitis  exists.  A  fetid  bronchitis  develops  from  a 
bacterial  decomposition  of  the  exudate.  From  the  stand- 
point of  course  catarrhal  bronchitis  may  be  either  acute 
or  chronic,  and  from  the  causes  a  verminous  and  a  mycotic 
bronchitis  may  be  distinguished. 

Etiology. — The  causes  are  usually  refrigeration  (changeable 
weather),  inhalation  of  mechanical  and  chemical  irritants 
(dust,  smoke,  chemical  fumes),  aspiration  of  fluids  such  as 
liquid  medicines  unskilfully  administered,  blood,  pus  or 
solid  matter  such  as  food  which  gains  access  to  the  windpipe 
especially  when  the  pharynx  is  paralyzed.  Certain  animal 
parasites  (strongylus)  and  bacteria  are  also  causes. 

Secondary  bronchitis  occurs  with  most  of  the  infectious 
diseases  affecting  the  respiratory  tract  (influenza,  strangles, 
tuberculosis,  hog  cholera). 


30  DISEASES  OF  THE  BRONCHI 

Symptoms. — The  characteristic  symj)t()ins  of  acute  catar- 
rhal hroncliitis  are  cough,  which  is  at  first  short,  dry  and 
and  ])aint'ul,  l)ut  later  with  the  accumulation  of  li(iuid 
exudate  becomes  looser  and  less  ])ainful.  Nasal  discharge 
is  present  and  during  the  act  of  coughing  bronchial  slime 
is  ejected  through  the  mouth  and  nose.  In  the  early  stages 
especially  the  res])irati()ns  are  increased.  Percussion  is 
normal  and  on  auscultation  rales  are  heard.  Rales  may  be 
absent  in  the  early  stages  but  will  appear  generally  about 
the  second  or  third  day.  The  character  of  the  rale  will 
depend  ui)on  the  size  of  the  bronchus  involved  and  the 
consistency  of  the  exudate.  In  the  larger  bronclii,  provided 
the  exudate  is  rather  thin  fluid,  the  rale  is  of  the  character 
of  bursting  large  bubbles,  while  in  the  smaller  bronchi  the 
rales  are  much  finer  and  of  a  crepitant  character.  If  the 
bronchial  mucosa  is  much  swollen,  narrowing  the  lumen  of 
the  bronchi,  whistling,  piping  or  hissing  tones  may  be  heard. 
As  a  rule  the  animal  shows  fever  in  the  early  stages  (104°  to 
106°  F.),  but  usually  within  two  or  three  days  the  tempera- 
ture drops.  With  the  continuance  of  the  fever  the  pulse 
frequency  increases. 

Chronic  Catarrhal  Bronchitis. — Chronic  catarrhal  bron- 
chitis usually  develops  from  the  acute  form.  It  may  occur, 
however,  as  a  symptom  of  chronic  heart  and  lung  disease. 
It  is  very  frequently  associated  with  chronic  i)ulm()nary 
emphysema  or  seen  to  accompany  such  chronic  infectious 
diseases  as  tuberculosis,  glanders,  or  verminous  ])neumonia. 
Generally  speaking,  chronic  bronchitis  leads  to  irreparable 
injury  not  only  of  the  walls  of  the  bronchi  but  of  the  neigh- 
boring lung  tissue  (parabronchitis,  bronchiectasis,  atelectasis, 
emphysema).  The  symptoms  of  chronic  bronchitis  are 
much  the  same  as  those  of  the  acute  except  that  the  condi- 
tion is  feverless  and  sufi'ers  many  exacerbations  and  remis- 
sions. The  general  condition  of  the  patient  may  not  be 
much  disturbed,  and  the  only  evidences  of  the  disorder  are 
chronic  cough,  dyspnea,  and  nasal  discharge  which  is  often 
foamy  and  white  in  appearance.  Obviously  if  chronic 
bronchitis  is  a  symptom  of  an  infectious  disease  like  tuber- 
culosis or  glanders,  the  symptoms  which  typify  these  con- 


CATARRHAL  BRONCHITIS  37 

ditions  will  be  associated  with  those  of  bronchitis.  In 
practice  chronic  bronchitis  is  most  commonly  met  with  in 
horses  suffering  from  "heaves"  (pulmonary  emphysema). 
It  also  occurs  frequently  in  dairy  cows  in  the  eastern  States. 

Course. — The  acute  form  usually  terminates  in  two  to  three 
weeks  in  healing.  When  the  smaller  bronchi  become 
involved  (bronchiolitis)  the  course  is  more  prolonged  and  is 
apt  to  lead  to  bronchopneumonia  and  death.  Death  may 
also  result  from  pulmonary  edema. 

Chronic  bronchitis  may  last  for  months  or  years,  depend- 
ing upon  the  cause.  Generally  in  time  the  patient  becomes 
anemic,  cachectic,  and  finally  death  results  from  inanition. 

Diagnosis. — The  diagnosis  of  bronchial  catarrh  is,  as  a  rule, 
not  difficult.  The  presence  of  the  characteristic  rales  or 
rhonchi  are  evidence  enough,  especially  when  taken  into 
consideration  with  the  other  symptoms  and  course  of  the 
disease.  It  is  sometimes  impossible  to  determine  whether 
the  bronchitis  is  primary  or  secondary.  Generally,  however, 
when  bronchitis  is  secondary  to  some  acute  infectious  disease 
the  high  temperature  which  the  patient  shows  is  indicative. 
When  associated  with  a  chronic  infection  a  thorough  clinical 
examination  of  the  patient  will  usually  reveal  the  presence 
of  a  primary  disease  (tuberculosis,  tuberculin  test;  glanders, 
various  tests). 

Prognosis. — A  primary  catarrh  of  the  larger  bronchi  is 
usually  more  benign  than  that  of  the  bronchioli.  In  very 
young  or  very  old  animals  on  account  of  the  prevalence  of 
bronchiolitis  the  prognosis  is  not  as  good  as  in  animals  in 
the  prime  of  life.  Bronchitis,  the  result  of  inhalation  of 
smoke  or  fire,  is  usually  diffuse  and  dangerous.  If  pneu- 
monia develops,  which  is  not  common,  obviously  the  prog- 
nosis is  not  so  good. 

Bronchites  which  are  secondary  are  governed  from  a 
prognostic  standpoint  by  the  course  of  the  primary  disease. 
Treatment.— The  patient  should  be  kept  in  a  light,  clean, 
well-ventilated  place  and  every  attention  given  the  hygiene 
of  the  skin.  The  horse  should  be  covered  with  a  light 
blanket  and  the  legs,  if  cold,  rubbed  and  wrapped  in  soft 
bandages.     If  the  dyspnea  is  marked   an  oil   of  mustard 


38  DISEASES  OF  THE  BRONCHI 

infriction  (1  to  12)  should  be  applied  to  the  chest.  The  food 
should  be  laxative  (bran,  oats,  grass,  carrots).  The  bowels 
should  be  kept  open  by  usinij;  Carlsbad  salts.  If  the  coufi^h 
is  drj'  and  painful,  inhalants  (camphor,  turi)entine,  or 
creolin)  may  be  administered.  Of  value  in  dry  bronchitis 
is  temperate,  moist  air  which  may  be  created  with  a  spray 
or  placing  water  in  buckets  in  the  stable.  Tartar  emetic 
combined  with  heroin  is  of  some  use  as  an  expectorant 
and  to  allay  distressing  cough.  The  following  prescription 
is  suggested. 

I^ — Heroini gr.  viij 

F.  E.  hyoscyami  or  belladonntB 5j 

Ant.  et  potassi  tart 3iv 

Syrupi q.  s.  Oj 

Sig. — One  ounce  every  two  hours. 

If  the  cough  is  troublesome  treat  as  indicated  in  laryngitis. 
Intratracheal  injections  are  of  little  value,  as  the  fluid  does 
not  reach  beyond  the  larger  bronchi.  If  the  accumulation 
of  liquid  exudate  is  excessive  a  hypodermic  of  atropin  (gr.  j) 
will  temporarily  arrest  the  discharge  and  dyspnea. 

Chronic  bronchitis  is  usually  incurable.  Expectorants, 
diuretics  and  sedatives  often  used  combined  may  tempo- 
rarily alleviate  the  symptoms.     (For  details  see  Heaves.) 


'  VERMINOUS   BRONCHITIS. 

LuNG-woR.M  Plague. 

Definition. — A  form  of  bronchitis  due  to  the  presence  of 
palisade  worms  in  the  air  tubes.  There  is  usually  associated 
with  it  bronchopneumonia. 

Occurrence. — The  disease  is  very  common  in  all  countries 
and  assumes  the  form  of  an  enzootic,  causing  great  losses 
among  sheep,  cattle  and  more  rarely  swine.  Horses  and 
asses  are  rarely  affected.  The  lung-worm  plague  is  most 
apt  to  follow  after  wet  summers  and  among  animals  kept 
in  swampy  pastures  or  lands  subject  to  overflow.  Outbreaks 
have  occiM'rcd,  however,  among  stabled  sliecp. 


VERMINOUS  BRONCHITIS  ^9 

Etiology.-From  a  clinical  standpoint  the  following  varie- 
ties of  the  nematode  worm  are  important. 

1 .  Strongylus  filaria  of  sheep. 

2.  Strongylus  micrurus  of  cattle. 
3    Strongylus  paradoxus  of  swine. 

The  life  historv  is  not  entirely  known.     These  parasites 
which   are  long,  slender,  filiform  worms,  in  the  adult  stage 
inhabit  the  bronchi  and  trachea.     Their  eggs  and  embryos 
are  eliminated  from  the  body  by  coughmg  and  with  the^  eces. 
Outside  of  the  body  they  probably  undergo  changes      Sheep, 
cattle  and  swine  take  them  up  with  food  and  water  of  infested 
pastures,  feed  boxes,  stable  floors,  etc.     The  parasites  pass 
first  to  the  stomach;  probably  during  rumination  they  reach 
the  pharynx,  trachea,  and  bronchi.     It  is  also  probable  that 
he  embryos  are  carried  to  the  lungs  by  Uie  blood,  as  nodules 
containing  them  are  not  infrequently  found  in  the  lungs. 
In  about  two  months  after  ingestion  the  strongylus  becomes 
sexually  ripe.     The  worm  brood  is  usually  taken  into  the 
body  during  the  spring  and  the  climcal  symptoms  o    the 
disorder    produced    develop    two    to    three    months    later. 
Infestation,  however,  is  possible  during  the  summer  or    all 
Young  animals  (lambs  and  calves)  are  more  susceptible      an 
adults.     Suckling  lambs  and  calves  may  be  infected  from 
the  udders  of  their  dams. 

Necropsy.-On  necropsy  the  lungs  of  affected  sheep  show 
chronic  bronchitis  with  bronchiectasia  and  usually  catarrhal 
pneumonia  and  nodular  parabronchitis.  The  cadaver  m 
the  later  stages  of  the  disease  is  anemic  and  hydremic, 
transudates  occurring  in  the  body  cavities  and  the  connective 
tissue  There  is  obviously  evidence  of  bronchitis,  the 
bronchial  tubes  being  partially  filled  with  mucopurulen 
exudate.  Numbers  of  sexually  mature  worms  are  present 
and  under  the  microscope  ova  and  embryos  can  be  seen. 

Symptoms.-In  practice  outbreaks  affecting  herds  of 
lambs  and  calves  usually  occur  in  the  summer  and  fall,  ihe 
early  symptoms  are  those  of  a  chrome  bronchial  catarrh, 
the  patient  coughing,  showing  nasal  discharge  and  on  auscul- 
tation rales  are  heard.  Later  the  affected  animals  become 
emaciated,  anemic,  hydremic  (cold  edemas  under  the  throat 


40  DISEASES  OF  THE  BRONCHI 

and  brisket),  dyspneic  and  cachectic.  The  symptoms  in 
calves  are  much  the  same  as  those  in  lambs. 

Diagnosis. — A  positive  diagnosis  can  be  made  only  on 
necr()])sy  or  by  micr()sco])ic  examination  of  the  feces  or 
broncliial  exudate  couglied  u])  by  the  patients. 

Prognosis. — The  prognosis  depends  upon  the  severity  of 
the  sym{)t()ms  and  the  age  and  condition  of  the  patient. 
The  disease  is  much  more  serious  in  lambs  and  calves  than 
in  pigs.  Adult  animals  frequently  recover  spontaneously. 
In  lambs  the  mortality  will  vary  from  10  to  70  per  cent, 
in  diti'erent  outbreaks;  in  calves  the  prognosis  is  more  favor- 
able. 

Treatment. — The  most  elective  treatment  consists  in 
intratracheal  injections  of  antiparasitic  drugs.  The  use  of 
a  spray  or  the  inhalation  of  sulphur  fumes,  smoke  from 
bin-ning  feathers,  etc.,  affords  usually  only  temporary  relief. 
The  following  mixtures  may  be  used  intratracheally: 

T\ — Ol.  tprebinthinie, 

Ol.  olivte afi      Jiij 

Creolini oiiss 

M.  Sig. — Inject  into  the  traclioa  't  cc  lor  lambs,  20  cc.  for  calves;  repeat, 
twice  at  four-(la.\'  intervals. 

H — ("reosoti 0^' 

Ol.  oliva> oi'.i 

M.  Sitr. — Intratracheal  injection  '»  c.c.  for  lambs,  15  to  20  c.c.  for  calves; 
rei)eat  in  four  days. 

Potassium  picronitricum  1  per  mille  has  given  good  results 
(20  to  00  c.c.  according  to  age). 

Prophylaxis. — The  sheep  and  lambs  should  be  removed 
from  infested  pastures  and  fed  highly  nutritious  food. 
Water  should  be  supplied  from  a  well  and  dry  pavement 
kept  about  the  drinking  troughs.  'J'he  sheei)  pens,  lots, 
mangers,  floor,  etc.,  should  be  thoroughly  disinfected.  If  the 
floor  is  of  earth  it  should  be  removed  to  the  depth  of  six 
inches  and  filled  in  with  fresh  uninfested  clay  or  cemented. 
Infested  fields  should  be  thoroughly  tile-drained  and  culti- 
vated. ]\Iany  sheep  owners  recommend  that  tobacco 
leaves  mixed  with  salt  be  made  accessible  to  the  sheep  at  all 
times.  Sulphate  of  iron  and  salt  ma>'  be  fed  once  weekly 
with  the  grain. 


CHAPTER   IV. 
DISEASES  OF  THE  LUNGS. 

CIRCULATORY   DISTURBANCES   IN   THE   LUNGS. 

Congestion  of  the  Lungs. — Definition. — An  engorgement  of 
the  pulmonary  capillaries  with  blood.  It  may  be  active  or 
passive. 

Etiology. — Active  congestion  is  due  to  increased  heart 
action  which  may  be  brought  about  by  overexertion  in 
unconditioned  horses  (racing,  hard  pulling)  especially  during 
hot  weather.  Heat  stroke  may  induce  it.  The  inhalation 
of  irritant  gases  (stable  fires)  is  a  cause.  The  first  stage  of 
pneumonia  is  congestion  of  the  lungs. 

Passive  congestion:  Two  forms  may  be  recognized, 
mechanical  and  hypostatic. 

INIechanical  congestion  occurs  whenever  there  is  some 
condition  of  the  heart  present  which  prevents  the  free  return 
of  blood  to  it  (left  valvular  stenosis;  mitral  insufficiency). 
It  may  arise  from  any  heart's  weakness  (cloudy  swelling, 
dilatation),  and  occur  during  the  course  of  an  acute  infectious 
disease  which  aft'ects  the  heart.  Passive  congestion  may 
follow  filling  of  the  pericardium  (pericarditis)  and  be  second- 
ary to  gastric  or  intestinal  bloat. 

Hypostatic  congestion  occurs  in  large  animals  when  the 
patient  lies  in  one  posture  for  a  long  time,  the  blood  gravitat- 
ing to  the  lower  lung.  Probably  the  attending  heart's 
weakness  assists. 

PULMONARY  EDEMA. 

Definition. — A  transuding  of  serum  into  the  alveoli  and 
bronchioli.  It  is  the  next  step  in  congestion,  which  it 
accompanies;  it  also  occurs  in  pneumonia. 


42  diseased;  of  the  lvxos 

Etiology. — Edema  usually  follows  congestion,  the  advanced 
sta<jes  of  which  it  represents  (serous  pneumonia) .  The  causes 
are,  therefore,  those  of  conji^estion  and  ])neum()nia,  i.  r., 
inhalation  of  irritant  gases,  acute  infectious  diseases  (malig- 
nant edema,  anthrax);  may  attend  severe  acute  nephritis; 
any  heart  weakness;  bronchial  parasites  (Str.  paradoxus  in 
swine). 

Symptoms. — As  pulmonary  congestion  and  edema  are 
always  more  or  less  combined,  their  symptoms  may  be 
treated  together.  They  are:  Dyspnea  which  develops 
rapidly.  Sometimes  the  patient  becomes  apneic.  The 
respirations  may  reach  80  to  100.  If  the  edema  is  well 
develo])ed,  there  is  a  foamy,  blood-tinged  nasal  discharge. 
The  mucous  membranes  may  be  cyanotic.  The  heart 
beat  is  often  palpitating,  the  pulse,  at  first  full  and  rapid, 
later  becomes  weak.  Percussion  is  normal.  Auscultation: 
exaggerated  vesicular  breathing,  crepitant  rales,  moist 
rales. 

Course. — May  be  very  rapid,  especially  if  it  follow  active 
congestion.  In  six  to  twelve  hours  the  symptoms  may 
abate  or  lead  to  death.  Following  passive  congestion,  the 
course  may  be  four  to  six  days  with  lethal  termination. 
Apoplectic  death  may  also  occur.  Rarely  pneumonia 
develops. 

Diagnosis. — The  dyspnea,  sudden  onset  and  usually  rapid 
course  are  characteristic.  From  acute  bronchitis  it  is 
distinguished  by  the  absence  of  fever  and  distressing  cough 
and  the  presence  of  crepitant  rales  and  foamy  nasal  dis- 
charge. Heat  stroke  resembles  it  but  the  high  tcmi)erature 
(may  reach  1 12°  F.)  and  nervous  i)rostration  of  this  condition 
are  sufficient  for  dillerentiation. 

Prognosis. — Usually  good  in  robust  patients.  A  weak 
pulse  and  fever  are  bad  signs.  Pulmonary  congestion  and 
edema  arc  often  fatal. 

Treatment.  Bleeding  is  indicated  when  the  <lysj)nca  is 
very  great.  In  large  animals  remove  4  to  (i  quarts  of  blood 
from  the  jugular.  Its  affect  is  often  life-saving.  The 
a|)plicati()n  of  oil  of  mustard  to  the  chest  is  heli)ful.  While 
the    heart    is   weak    lmvc   excitants    (alcohol,  ether,  cafl'cin). 


PULMONARY  EDEMA  43 

Sulphate  of  atropin  (gr.  \  to  \  subcutaneously)  is  good  in 
cases  where  edema  predominates  (foamy  nasal  discharge). 
Digitalis  and  strychnin  are  also  recommended.  In  milder 
cases  an  aloes  ball  affords  relief.  Nitroglycerin  (gr.  \  to  j) 
is  sometimes  used. 

Bronchopulmonary  Hemorrhage  (Bronchorrhagio,  Pneu- 
morrhagia,  Bleeding  from  the  Lungs,  Hemoptysis). — Definition. 
— Bleeding  from  the  lower  air  passages  and  lung  tissue. 

Etiology. — Bleeding  from  the  bronchial  mucous  mem- 
brane may  be  due  to  overexertion,  as  fast  driving,  racing. 
It  is  seen  in  valvular  heart  disease,  congestion  of  the  lungs, 
aneurysms  (aorta,  pulmonary  artery),  lung  infarctions, 
thrombosis,  embolism.  In  infectious  diseases  it  is  at  times 
a  symptom  (fibrinous  pneumonia,  purpura  hemorrhagica, 
anthrax,  glanders,  tuberculosis).  Where  caverns  of  the  lung 
remain  after  pneumonia,  hemorrhage  occurs.  Frequently 
no  cause  can  be  found  on  postmortem  to  explain  the  hemor- 
rhage. 

Symptoms. — Bleeding  from  the  nose  is  the  principal 
symptom.  If  the  blood  comes  from  the  larger  bronchi,  it 
will  flow  from  the  nostrils  in  drops  or  in  a  thin  stream  and 
is  usually  not  frothy.  From  the  finer  bronchi  and  lung  the 
blood  is  frothy  and  of  light  red  color.  The  patient  is  dyspneic 
and  coughs.  On  auscultation  rales  are  heard.  Percussion 
normal. 

Treatment. — The  patient  should  be  kept  as  quiet  as 
possible.  Ice  packs  (or  cold  water)  may  be  applied  to  sides, 
vulva  or  scrotum  (reflex  affect).  Internal  medication  does 
little  good,  Ergot  in  the  form  of  fluidextract  is  recom- 
mended by  most  practitioners;  others  condemn  it.  Acetate 
of  lead  (5j)  given  three  times  daily  is  employed  in  obstinate 
cases.  Sulphuric  acid  (dilute  5vj)  is  sometimes  beneficial. 
Theoretically  aconite  (Fleming's  tincture  TTlx)  is  good  as  it, 
lowers  blood-pressure.  Lung  hemorrhages  which  are  due 
merely  to  congestion  of  the  bronchial  mucous  membrane 
or  lung  usually  stop  spontaneously  when  the  blood-pressure 
becomes  low.  On  the  other  hand,  those  hemorrhages  due  to 
a  ruptured  vessel  in  the  lung  (aneurysm)  are  generally 
copious  enough  to  produce  death. 


44  DISEASES  OF   THE  LUNGS 

PULMONARY   GANGRENE. 

Definition. — A  (le{'oiiii>()siti()ii  of  tlie  dead  lung  tissue  due 
tt)  tlie  inicroorganisins  of"  putrefaetion. 

Occurrence. — Most  often  in  horse,  swine,  and  sheep. 

Etiology.  -]\ lay  result  from  fibrinous  pneumonia,  diseases 
of  the  ])harynx  which  make  swallowinji;  difficult  (pharyngitis, 
I)aralysis),  general  diseases  affecting  the  j)harynx  (tetanus, 
l)arturient  paresis,  forage  poisoning)  causing  the  food 
swallowed  to  "go  the  wrong  way;"  the  aspiration  of  foreign 
matter  (dust,  sawdust,  blood,  pus,  grains,  hair,  plant 
fibers,  etc.),  drenches  unskilfully  administered  (pneumonia 
medicantaria)  especially  in  horses,  sheep,  and  swine;  by 
metastasis,  emboli  develop  from  ulcerative  processes  in  the 
bowel,  hoof  matrix  (gangrenous  pododermatitis),  and  bone 
(caries).  In  these  instances  the  necrosis  bacillus  is  active. 
Traumatic  injuries  rarely  cause  jjulmonary  gangrene. 

Symptoms. — The  most  characteristic  symptom  is  fetid 
expirium.'  There  is  nasal  discharge  of  a  muddy  reddish- 
brown  or  greenish  color.  The  discharge,  which  is  more 
copious  after  coughing,  has  a  fetid  odor.  It  contains  bits  of 
dead  lung  tissue,  fat  crystals,  pigment,  and  innumerable 
microorganisms.  Under  the  microscope  elastic  fibers  are 
seen.  The  respirations  are  dyspneic  especially  in  the 
latter  stages  (toxemia).  Fever  is  nearly  always  present. 
It  is  usually  about  104°  to  105°  F.,  and  assumes  an  inter- 
mittent type.  In  gangrene  due  to  aspirated  foreign  matter, 
the  temperature  may  not  be  over  102°  F.  for  several  days. 
The  pulse  is  frequent,  arhythmic,  and  thready,  (^hills  are 
frequent.  The  i)atient  loses  flesh  rapidly,  is  weak,  languid, 
and  stupid.  The  appetite  is  capricious;  toward  the  end 
there  is  diarrhea.  Pregnant  animals  often  abort.  On 
percussion  the  sound  is  flat  over  the  ventral  and  middle 
portions  of  the  lung.  Sometimes  over  caverns  the  "  cracked- 
])ot"  tone  is  emitted.  On  auscultation  rales  and  tubular 
breathing  are  most  often  noted. 

*  If  the  Kaiigreiious  mass  does  not  eomnninicate  witli  a  hronchus  the 
expirium  may  not  be  fetid.  Diagnosis  in  these  cases  is  very  difficult  or 
imi)ossil)le. 


ABSCESS  OF   THE  LUNG  45 

Diagnosis. — The  finding  of  elastic  fibers  in  the  nasal  dis- 
charge is  pathognomonic.  The  fetid  breath  and  nasal 
discharge  are  indicative.  In  putrid  bronchitis  there  are 
usually  no  general  symptoms  such  as  fever  and  the  condition 
of  the  patient  is,  as  a  rule,  good. 

Prognosis. — Bad.  Only  when  local  foci  are  present  is 
encapsiilement  or  the  ejection  of  the  dead  mass  by  coughing 
probable. 

Treatment. — Unsatisfactory.  The  inhalation  or  intra- 
tracheal administration  of  antiseptics  may  be  tried.  Pneu- 
motomy  is  employed  in  man.  Give  good  food  and  care  and 
treat  the  heart,  bowel  (diarrhea)  and  fever  as  the  indications 
warrant. 

ABSCESS    OF   THE   LUNG. 

Definition. — Collection  of  pus  in  cavities  in  the  lung. 

Etiology. — Embolic,  metastatic  abscesses  following  general 
pyemic  diseases  (strangles,  purulent  metritis,  bacillosis  of 
sucklings),  or  secondary  to  primary  abscess  (abscess  within 
hoof,  abscess  following  castration).  It  is  rarely  due  to 
fibrinous  pneumonia,  but  may  follow  catarrhal  pneumonia 
due  to  foreign  matter  entering  the  bronchi,  especially 
medicines. 

Symptoms. — Abscess  following  pneumonia  is  recognized  by 
the  continued  fever  and  purulent  nasal  discharge.  The 
symptoms  are  usually  acute  (like  an  acute  pneumonia)  and 
much  resemble  those  of  pulmonary  gangrene. 

Diagnosis. — A  copious  nasal  discharge  which  is  largely 
made  up  of  pus  is  the  chief  clinical  feature  which  distinguishes 
it  from  pulmonary  gangrene. 

Course. — Usually  death  in  seven  to  ten  days.  Isolated 
abscesses  may  become  encapsulated  or  break  into  a  bronchus 
and  be  discharged.     Diagnosis  in  these  instances  is  difficult. 

Treatment. — Usually  of  little  avail.  In  man  well  defined, 
superficial  abscesses  are  surgically  treated  by  opening  and 
draining.  The  use  of  antiseptics  as  inhalations  (bichlorid, 
1  per  mille,  as  a  spray)  or  intratracheal  injections  are  sug- 
gested. 


40  DISEASES  OF  THE  LUNGS 

CHRONIC- ALVEOLAR   EMPHYSEMA. 

Definition. — Clironic  alveolar  emphysema  is  a  permanent 
overdisteiitioii  of  the  alveoli  with  an  increased  amount  of 
air  present  in  the  lung.  'I'he  walls  of  the  alveoli  become 
anemic  and  atrophic. 

Occurrence. — Most    common    in    horses,    especially    old, 
hard-worked  individuals.     It  is  a  common  cause  of  so-called 
heaves. 

Etiology. — (a)  Continued  severe  exercise  (hard  pulling, 
fast  flriving,  high  jumping).  This  causes  repeated  physio- 
logical dysj)nca  inducing  overdistention  at  inspiration  and 
causes  the  expiration  to  become  forced.  These  two  factors 
in  time  lead  to  weakening  and  finally  atrophy  of  the  alveolar 
walls.  The  alveoli  can  be  ten  times  their  normal  diameter, 
the  walls  very  thin  and  anemic.  Later  rupture  of  the 
interalveolar  septa  occurs,  permitting  direct  communication 
between  the  distended  air  cells.  The  lung  thus  loses  its 
power  of  contraction  at  expiration,  which  causes  this  act  to 
become  forced  so  that  the  air  from  the  emjjhysematous 
part  of  the  lung  is  ex])elled.  (b)  Severe  dyspnea  due  to 
diseases  of  the  larynx  or  bronchi  is  a  rare  cause,  (c)  Severe 
coughing,  especially  in  chronic  bronchitis,  (d)  Occasionally 
chronic  alveolar  emjihysema  results  from  the  acute  form. 
(e)  The  feeding  of  bulky  forage,  i)articularly  clover  or 
dusty  timothy  hay  is  no  doubt  an  important  predisposing 
cause  of  pulmonary  emphysema,  the  dilatation  of  the 
stomach  and  bowels  which  such  foods  produce  interfering 
with  respiration.  (/)  As  some  strains  of  horses  seem  more 
subject  to  emphysema  than  others,  an  inherited  predisposi- 
tion (lacking  resistance  in  the  septa)  has  been  assumed. 
Of  this,  however,  there  is  no  substantial  proof.  Use  and 
feeding  methods  may  explain  the  assumption. 

Symptoms. — Dyspnea  which  increases  on  exercise.  It  is 
always  most  pronounced  at  expiration  and  is  often 
accompanied  by  a  double  movement  of  the  flanks  and 
the  interrupted  protrusion  of  the  anus.  The  first  part 
of  the  expiratory  act  is  passive,  but  after  a  very  brief 
pause  the  movement  becomes  active,  the  abdominal  muscles 


CHRONIC  ALVEOLAR  EMPHYSEMA  4/ 

contracting  with  \igor  in  an  effort  to  compensate  for  the 
lost  elasticity  of  the  lung  and  to  expel  the  air.  A  marked 
groove  appears  along  the  costal  arches  ("heave  line"). 
The  inspiratory  act  is  shorter  than  the  expiratory.  The 
ribs  are  seen  to  roll  forward  beneath  the  skin,  the  intercostal 
spaces  deepen  and  the  ventral  portion  of  the  thorax  and  the 
anterior  aperture  of  the  chest  sink  inwardly.  In  advanced 
cases  the  ribs  are  kept  rolled  forward,  the  thorax  appearing 
barrel- shaped.  If  bronchitis  is  present,  there  is  cough  which 
is  usually  short,  weak,  and  dull.  The  cough  is  often  attended 
by  the  discharge  of  flatus  through  the  anus  ("breaking 
wind").  The  heart  sounds  are  at  times  feebler  than  normal. 
The  diastolic  sound  may  be  accentuated.  Percussion  gives 
a  sound  which  is  too  full  and  drum-like  (h^-perresonance). 
The  heart's  dulness  may  be  obliterated.  Posteriorly,  the 
area  of  the  field  of  percussion  is  enlarged,  the  post ero ventral 
limits  extending  through  the  18th,  17th  and  14th  ribs  at  the 
heights  on  the  thorax  of  the  external  angle  of  the  ilium, 
tuberosities  of  the  ischium  and  shoulder-joint  respectively. 
(With  normal  lungs  the  figures  would  read  17,  15,  and  11.) 
Auscultation:  If  the  bronchitis  is  present,  dry  or  moist 
rales  are  heard,  otherwise  the  vesicular  murmur  is  weakened. 
When  the  bronchi  are  involved  there  is  a  bilateral,  white 
nasal  discharge.  The  general  condition  suffers  in  old  cases. 
The  patient  loses  flesh,  becomes  anemic  with  a  tendency 
for  edema  to  form  under  the  chest  and  belly  and  in  the 
limbs. 

Course. — The  course  is  prolonged,  the  condition  lasting 
for  months  and  years.  Once  affected  the  patient  never 
fully  recovers.  The  symptoms  improve  as  the  attending 
bronchitis  improves,  the  patient's  work  lightened  and  the 
quantity  of  roughage  fed,  especially  tame  hay,  reduced. 
On  the  other  hand  exposure,  hard  work  and  the  feeding 
of  bulky,  dusty  food  (hay),  and  allowing  the  thirsty  patient 
to  drink  at  one  time  all  the  water  it  will,  greatly  increases 
the  dyspnea  and  cough. 

Diagnosis. — Only  advanced  cases  can  be  diagnosed.  The 
characteristic  dyspnea,  which  increases  on  exercise,  the 
dilated   nostrils,   the  anal  protrusion,   cough,   and  absence 


4S  DISEASES  OF   THE  JA'XCS 

of  fever  are  characteristic.  Its  clironicity  (absence  of  fever) 
and  pliysical  signs  (auscultation  and  percussion)  differentiate 
emphysema  from  acute  febrile  diseases  of  the  respiratory 
system  (])leuritis). 

Prognosis. — As  far  as  the  life  of  the  patient  is  concerned 
the  prognosis  is  good,  but  from  the  standjjoint  of  healing 
there  is  no  hope  of  a  permanent  cure.  Difl'use  bronchial 
catarrh  and  weak  heart  are  bad  complications. 

Treatment. — No  treatment,  hygienic,  dietetic  or  medicinal 
will  cure  chronic  pulmonary  emphysema.  By  using  the 
patient  only  for  light  work,  feeding  good  nutritious  food 
(clean  oats,  bran),  allowing  only  small  quantities  of  dustless 
(moistened)  hay,  and  watering  frequently  but  in  small 
quantities  at  a  time,  the  symptoms  may  be  overcome  so 
long  as  the  above  dietetics  are  persisted  in. 

Drugs. — There  are  several  drugs  such  as  belladonna, 
datura  stramonium,  hyoscyamus,  which  contain  atropin, 
that  will  mask  the  symptom^  (dyspnea)  in  a  marked  degree. 
By  using  such  drugs  horse-traders  often  deceive  prospective 
buyers  into  believing  the  horse  to  have  "good  wind."  How- 
ever, the  abatement  of  the  symptoms  is  only  temporary, 
lasting  usually  but  one  day.  The  abnormal  dilatation  of 
the  pupil,  dryness  of  the  mucous  membranes  and  rapid  pulse, 
which  usually  follow  the  use  of  a  "dope,"  should  put  the 
veterinarian  on  his  guard. 

Arsenic  is  useful,  usually  given  in  the  form  of  Fowler's 
solution  (5ss)  three  times  daily  in  the  drinking  water. 
Subcutaneous  injections  of  atropin  temporarily  allay  the 
symptom.  Treating  the  attending  bronchial  catarrh  is 
helpful  (see  this).  In  "heavy"  horses  avoid  using  arecalin, 
eserin,  or  barium  chlorid. 


ACUTE   INTERSTITIAL   PULMONARY   EMPHYSEMA. 

Definition. — Kupture  of  the  alveoli  with  the  entrance  of 
air  into  the  interstitial  tissue  of  the  lung,  bubbles  appearing 
beneath  the  pleura. 

Occurrence. — Has  been  noted  in  horse  and  ox. 


INFLAMMATION  OF   THE  LUNGS  49 

Etiology. — Anything  which  greatly  increases  air  pressure 
in  the  alveoli.  Violent  coughing  fits  to  dislodge  foreign 
bodies,  medicine,  etc.,  which  have  gotten  into  the  bronchi. 
It  rarely  accompanies  acute  catarrhal  and  croupous  bron- 
chitis. Violent  contractions  of  the  abdominal  muscles 
(hard  pulling,  retching,  continued  bellowing  in  cattle). 
Violent  struggles  to  get  free  from  hobbles,  or  if  a  horse  is 
cast  in  the  stall  and  makes  vigorous  efforts  to  free  itself. 

Symptoms. — Sudden  dyspnea  which  may  rapidly  lead  to 
suffocation.  Emphysema  of  the  skin  (in  ox)  of  the  aperture 
of  the  chest,  shoulders,  and  side  of  thorax.  It  may  involve 
the  whole  trunk.  Percussion  is  practically  normal.  On 
auscultation  crackling  sounds,  rales. 

Course. — Usually  fatal  in  twenty-four  to  thirty-six  hours. 
Healing  only  in  less  acute  cases. 

Diagnosis. — Unless  subcutaneous  emphysema  develop, 
may  be  impossible.  Can  easily  be  confused  with  pulmonary 
congestion  and  edema.     The  history  is  helpful. 

Treatment. — Allay  cough.     Scarify  skin. 

INFLAMMATION    OF    THE   LUNGS. 

Pneumonia.    Pneumonitis. 

The  following  clinical  forms  of  pneumonia  may  be  distin- 
guished : 

Fibrinous. 
Catarrhal. 
Foreign  body. 
Metastatic. 
Interstitial. 
Fibrinous  Pneumonia  {Lung  Femr,  Croupous  Pneumonia). 
— Definition. — An   inflammation   of  the  lung  characterized 
by  its  typical  course,  and  the  formation  of  fibrinous  coagulse 
in  the  alveoli  of  the  invaded  area.     It  affects  the  lobe  rather 
than  the  lobule. 

Etiology. — The    existence    of   fibrinous    pneumonia    as    a 
primary  disease  in  animals  is  open  to  question.     At  any 
rate  it  has  not  been  proven. 
4 


50  DISEASES  OF   THE  LUNGS 

In  the  horse  it  is  usually  exi)ressive  of  infectious  fibrinous 
pneumonia  although  it  may  accompany  strangles  or  jjurjjura 
hemorrhagica. 

In  the  ox  it  most  commonly  is  noted  as  a  symptom  of 
hemorrhagic  septicemia  clue  to  the  Bacterium  hoviscpticum.' 
It  also  occurs  from  foreign  bodies  entering  the  lung  from  the 
reticulum,  the  aspiration  of  ingesta  in  choking  or  when  the 
pharynx  is  paralyzed. 

In  swine  it  is  a  symptom  of  hog  cholera  (lung  form), 
hemorrhagic  septicemia  and  anthrax.  A  mixed  fibrinous 
and  catarrhal  pneumonia  may  occur  in  swine  due  to  the 
aspiration  of  medicine  unskilfully  given  as  a  drench  (melted 
lard). 

In  sheep  fibrinous  pneumonia  is  seen  in  hemorrhagic 
septicemia  (Bacterium  ovisepticum). 

Cold,  the  inhalation  of  irritant  gases,  smoke,  steam,  etc., 
great  exhaustion  from  overwork,  casting,  tying  the  head  of 
the  horse  too  higli,  etc.,  are  merely  predisposing  factors 
in  the  etiology  of  fibrinous  pneumonia. 

Symptoms. — The  onset  of  the  disease  is  usually  sudden. 
Without  warning  the  patient  is  seized  with  fever,  which  in  a 
few  hours,  in  the  horse,  may  reach  104°  to  10()°  F.  The 
patient  is  stui)id,  languid,  and  loses  appetite.  In  some 
cases  a  pronounced  chill  ushers  in  the  disease  symptoms. 
The  fever  is  of  the  continuous  type  remaining  up  for  seven 
to  nine  days  when  it  drops  rapidly  to  normal  (by  crisis), 
or  on  the  third  or  fourth  day  may  begin  to  gradually  decline, 
reaching  normal  in  four  to  eight  days  following  (by  lysis). 
Cough  is  short,  painful,  and  frecjuently  restrained.  At 
first  it  is  dry,  later  moist  in  character.  Nasal  discharge 
is  not  always  present,  especially  in  continuously  stabled 
horses.  In  some  cases,  during  the  stage  of  red  hepatization, 
a  rusty  brown  ("prune  juice")  discharge  occurs  which  may 
last  only  twenty-four  to  forty-eight  hours.  In  the  stage  of 
resolution  a  yellow-colored  discharge  may  appear.  The 
pulse  at  first  is  not  much  aflVcted,  but  as  the  disease  pro- 
gresses, due  to  cloudy  swelling  of  the   heart,  its  frequency 

1  In  these  eases  the  pneumonia  is  a  mixture  oi  catarrhal  antl  (iljrinuus  and 
the  course  of  the  disorder  is  atypical. 


INFLAMMATION  OF   THE  LUNGS  51 

is  increased  to  60  to  SO  or  higher.  Quite  often  the  pulse 
remains  high  after  the  fever  has  gone  down.  The  respira- 
tions are  accelerated  early  and  the  patient  breathes  with 
distended  nostrils.  The  conjunctiva  in  severe  cases  often 
assumes  a  spotted  mahogany  color.  The  percussion  varies 
with  the  stage  of  the  disease.  In  the  earliest  stage  (con- 
gestion) there  is  little  appreciable  change  (somewhat  tympan- 
itic);^ in  the  second  stage  (hepatization)  a  flat  sound  is 
emitted.  The  sound  begins  about  the  second  day  and  is  re- 
tained three  to  five  days.  During  the  third  stage  (resolution) 
the  soimd  becomes  tym])anitic  again.  The  area  of  dulness 
is  usually  confined  to  the  ventral  portion  of  one  lung,  its 
dorsal  limits  often  describing  an  upward  curved  line.  Aus- 
cultation :  In  the  first  stage  crepitant  rales  at  inspiration — 
fine  crackling  sounds  like  rubbing  hair  between  the  fingers. 
.These  sounds  are  usually  present  for  the  first  twenty-four  to 
forty-eight  hours,  then  pass  away.  In  the  second  stage  the 
vesicular  murmur  is  gone  and  there  is  either  no  respiratory 
sound  audible  or  tubular  breathing  (bronchial)  is  heard.  In 
the  third  stage  moist  rales  are  heard  (the  return  rale). 
General  condition :  Varies  greatly  with  the  case.  In  mild 
attacks  the  appetite  may  be  retained  and  the  mind  little 
perturbed.  In  severe  cases  there  is  no  appetite  while  the 
fever  is  on,  and  the  animal  is  very  stupid  and  languid. 
Horses  usually  do  not  lie  down  until  the  fever  drops.  Small 
animals  and  even  ponies  lie  down  most  of  the  time  during  the 
disease,  and  if  only  one  lung  is  affected,  on  the  diseased  side. 
The  urine  is  scanty  and  high  colored  until  the  fall  of  the 
fever  when  its  specific  gravity  drops  and  the  quantity,  ^'oided 
frequently,  greatly  increases. 

Diagnosis. — Acute  catarrhal  pneumonia  may  be  confused 
with  it.  The  principal  differential  features  are:  (see  Table 
E.).  From  pleuritis  it  may  be  distinguished  by  auscultation 
and  percussion.  In  cases  complicated  with  pleuritis  (pleuro- 
pneumonia) differentiation  may  be  impossible.  However, 
pleuritis  is  usually  bilateral,  the  upper  margin  of  the  zone 

1  The  flat  percussion  sound  may  not  be  obtained,  if  the  pneumonia  involves 
the  central  rather  than  the  peripheral  portion  of  the  lungs  (pneumonia 
centralis). 


52  DISEASES  OF  THE  LUNGS 

of  dulness  on  percussion  is  horizontal  and  the  resistance 
under  the  hammer  pronounced.  In  pleuritis  there  is  further 
a  tendency  for  edema  to  form  in  pendent  parts  of  the  body. 
Cough  is  usually  absent  in  pleuritis;  present  in  pneumonia. 
A  test  puncture  of  the  thorax  may  be  made  in  doubtful 
cases. 

Complications. — (a)  Heart  weakness  due  to  cloudy  swel- 
ling. The  beat  is  fast,  arhythmic,  and  palpitating.  The 
l)ulse  may  be  weak  (thready)  and  runs  about  7(5.  The 
patient  is  weak,  may  be  cyanotic,  superficial  veins  distended. 

(6)  Pleuritis:  A  common  complication,  leading  to  effu- 
sion in  the  chest,  displacement  of  the  heart  and  characteristic 
dj^spnea.     (See  Pleuritis.) 

(c)  Gangrene  of  the  lung:  May  develop  during  convales- 
cence. The  temperature  again  rises,  the  patient  continues 
to  lose  flesh  and  the  expirium  assumes  a  sweetish,  fetid  odor. 

{(1)  Further  but  less  common  complications  are:  Xei)hritis 
(albumin  in  urine),  jaundice  (catarrh  of  duodenum),  tendo- 
vaginitis (leg  swelling  and  lameness),  founder,  cerebral  and 
meningeal  symptoms.  Purpura  hemorrhagica  may  occur 
during  convalescence. 

Course. — The  usual  course  is  tyj)ical,  ending  in  recovery 
in  two  weeks.  In  some  cases,  especially  in  old  horses,  cattle 
and  swine  the  course  may  be  much  shorter  (larval  or  abortive 
type).  Death  may  occur  suddenly  during  convalescence 
from  heart  failure.  If  i)leuritis  complicates  the  i)ncum()nia, 
the  course  is  much  j)rolonged.  It  may  lead  to  death,  or 
adhesions  (lung  to  thoracic  wall)  may  cause  permanent 
dyspnea   (heaves). 

Chronic  induration  of  the  lungs  is  a  common  termination 
following  certain  outbreaks.  It  is  characterized  by  the 
continuation  of  the  fever  and  dyspnea  after  the  usual  period 
of  convalescence  has  passed.  The  patient  is  generally 
left  short-winded.  Roaring  may  sometimes  follow  an 
attack  of  fibrinous  pneumonia.  Pericarditis  is  a  rarer  com- 
plication. The  prognosis  is  good  in  typical  and  uncom- 
plicated cases.  Of  importance  is  the  behavior  of  the  heart 
during  the  attack.  A  continued  high  ])ulse  is  dangerous  to 
the  patient.     The  extent  of  the  area  involved  has  much  to 


INFLAMMATION  OF   THE  LUNGS  53 

do  with  the  outcome  of  the  case.  If  confined  only  to  the 
ventral  portion  of  one  lung,  the  danger  is  not  so  great  as 
when  the  dorsal  part  of  the  lung  is  also  nivolved,  or  it  both 
lungs  are  diseased.  When  pleuritis  complicates  the  case 
the  prognosis  is  naturally  less  favorable. 

Treatment.— The  patient  should  be  placed  in  a  light,  clean 
and  well-ventilated  place.     If   feasible,  keep  the  case   out 
of  doors  as  much  as  possible,  guarding  it,  of  course,  against 
wind  and  rain.     Use  only  light  covering  (in  horses).     I  he 
legs  may  be  bandaged  (use  Derby  bandages  with  cotton 
underneath).     Removing    the    bandages    once    dai  y    and 
rubbing  the  legs  well   before   reapplying   is  helpful,     ihe 
horse-patient  should  be  groomed  well  each  day.     Feed  any 
easilv  digested  food  which  the  patient  can  be  coaxed  to  eat 
Good  clean  oats  over  which  a  little  sugar  has  been  sprinkled 
is  often  tempting  to  the  appetite.     Give  only  small  quantities 
at   a   time.     Before   feeding   syringe   out   the  mouth  with 
clean  water.     If  obtainable  fresh  grass  is  very  palatable  and 
nutritious.     A  few  handfuls  over  which  is  strewn  a  little 
salt  is  often  eaten  with  avidity.     The  hay  should  be  bright 
and  free  from  dust.     Feed  about  6  pounds  daily,  divided 
into  three  feeds.     Roots  (carrots,  beets)  and  bran  mashes 
are  recommended   (some  horses  do  not  like  bran).     Lggs 
and  milk  may  be  given  if  appetite  is  entirely  gone.     Keep 
pure  water  constantly  before  the  patient,  and  where  it  can 
be  gotten  at  without  undue  exertion.     Rectal  and  artificial 
feeding  may  be  resorted  to  in  patients  unable  to  swallow 
or  without  any  appetite. 

Drugs.— In  typical  cases  of  fibrinous  pneumonia  drugs  are 
often  not  only  superfluous  but  may  do  actual  harm. 

It  is  very  important  to  watch  carefully  the  heart.  Minor 
irregularities  may  be  overcome  by  small  doses  of  brandy 
(5ij)  mixed  with  ether  (3ij)  in  a  pint  of  water,  or  alcohol 
(5ij)  in  a  pail  of  drinking  water  may  be  kept  before  the 
patient,  especially  during  the  night.  It  may  be  repeated 
every  three  hours.  Digitalis  in  the  form  of  bquibb  s  hind 
extract  (3iv-vj),  giving  one  dose  only,  has  often  a  toning 
effect  upon  the  heart  (avoid  repeated  small  doses  of  this 
drug)      When  the  pulse  reaches  80  or  more  and  becomes 


54  DISEASES  OF   THE  LUNGS 

weak,  sul)t'utaiH'()iis  doses  of  the  oil  of  camj)hor  (5j)  are 
good.  Cafi'ein  (5j-5ij  subeutaneously)  is  useful.  For  great 
depression  (general  loss  of  arterial  tone— toxemia)  an  intra- 
venous infusion  of  normal  salt  solution  (2  to  4  quarts  in 
horse)  may  he  tried.  (If  heart  is  weak,  look  out  for  pul- 
monary edema.)  Subcutaneous  doses  of  ether  and  alcohol 
in  5ss  doses  are  valuable  in  this  condition. 

Unless  the  fever  be  unreasonably  high  (1()()°  to  108°  F.) 
or  threatens  the  heart's  force,  it  should  be  let  alone.  In 
robust  patients  cold  water  infusions  into  tlie  rectum,  cold 
compresses  over  the  chest  are  useful  in  reducing  the  tempera- 
ture a  degree  or  two.  Aeetanilid  (5iv  to  5j)  combined  with 
caffein  (5j)  is  recommended.     (Affect  depressing.) 

To  favor  resorption  of  the  exudate  diurectics  may  be 
employed.  Acetate  of  sodium  (5j  to  5j)  is  serviceable. 
Spirits  of  nitrous  ether  (5j)  is  recommended.  lodid  of 
sodium  (3iv)  is  useful.  In  delayed  resolution  the  resorption 
of  the  exudate  is  said  to  be  stimulated  by  puncturing  the 
infiltrated  lung  as  in  paracentesis  thoracis.  Local  ajiplica- 
tions:  In  severe  dyspnea  the  application  of  mustard  (oil  of 
mustard  in  alcohol  1-12-16)  is  advisable.  (Apply  in  airy 
room  and  use  light  blanket  over  patient  after  application.) 
An  ice-bag  over  heart  or  cold  compresses  changed  every 
fifteen  minutes  yield  good  results. 

During  convalescence  keep  the  animal  as  quiet  as  possible 
if  heart  be  weak  and  assist  the  appetite  and  digestion  by 
giving  artificial  Carlsbad  salts  to  each  pound  of  which  2 
ounces  of  nux  vomica  have  been  added.  For  treatment  of 
complications,  see  these. 

Catarrhal  Pneumonia  ( lirotichopnciniionid). — Definition. — 
An  inHaniination  of  the  hmgs  affecting  isolated  lobules  or 
grouj)s  of  lobules,  the  exudate  and  des(iuamate(l  cells  in  the 
abcoli  seldom  undergoing  fibrinous  coagulation. 

Occurrence. — Most  common  in  very  young  or  aged  animals. 
Less  frequent  in  the  horse  than  in  the  ox,  sheep,  and  swine. 

Etiology. — Catarrhal  ])neumonia  occurs  either  as  a  primary 
or  as  a  secondary  all'cction.  As  catarrhal  pneumonia  is 
clinically  a  collective  term  it  includes  a  group  of  jjueu- 
monias,  the  causes  of  which  are  varied.     It  inav  be  due  to: 


INFLAMMATIOX  OF   THE  LUNGS  55 

(«)  the  spreading  of  bronchitis  to  the  hnig  parenchyma;  (6) 
food  entering  the  wind  pipe  in  patients  suffering  from 
dyspliagia  (tetanus,  milk  fever,  feechng  too  soon  after 
chk)roform  narcosis);  (r)  foreign  matter  (dust,  sand,  saw- 
dust) which  may  l)e  drawn  into  the  lungs  in  recumbent 
patients;  {d)  the  aspiration  of  pus,  blood,  saliva  or  mucus 
(head  operations,  patient  recumbent) ;  (e)  unskilled  admini- 
stration of  medicines,  especially  drenches;  (/)  result  of 
hypostasis  of  the  lungs  (recumbent  position,  long  stable 
confinement  in  old  horses);  (g)  infection,  especially  with 
the  Bacillus  bipolaris  septicus  (in  the  ox)  and  the  Bacillus 
pyogenes. 

Cold,  bad  sanitation  and  exhaustive  railway  and  ship 
transportations  are  predisposing  factors. 

Catarrhal  pneumonia  is  secondary  to  several  acute  infec- 
tious diseases  as  malignant  head  catarrh,  hog  cholera, 
hemorrhagic  septicemia;  it  often  accompanies  tuberculosis, 
glanders,  and  occasionally  actinomycosis. 

Symptoms. — The  prodromal  symptoms  are  those  of 
bronchitis  which  it  usually  follows.  As  the  areas  of  solidi- 
fication in  the  lung  may  be  small  and  scattered,  they  are 
difficult  to  detect  clinically.  The  cardinal  symptoms  are: 
cough  which  is  short,  dull,  and  often  painful,  the  patient 
trying  to  suppress  it.  Nasal  discharge  which  is  at  times 
copious  and  white  in  color.  Fever  which  may  run  about 
104°  P".  The  fever  does  not  take  a  typical  course  as  in 
fibrinous  pneumonia,  but  is  intermittent  in  character,  con- 
tinuing until  the  termination  of  the  disease.  In  aged 
horses  fever  is  often  absent.  Dyspnea,  the  respirations  are 
accelerated,  and  labored.  Percussion  is  often  painful  and 
induces  coughing.  Areas  of  dulness  may  be  determined, 
provided  they  are  of  the  size  of  a  clenched  fist  and  super- 
ficially located  in  the  lung.  Auscultation:  rales  of  a  fine 
subcrepitant  and  whistling  character.  If  large  areas  of  the 
lung  are  involved,  bronchial  (tubular)  breathing  is  heard. 
If  the  bronchi  and  bronchioli  in  the  affected  area  are  plugged 
with  exudate,  no  sounds  will  be  emitted.  In  the  neighbor- 
ing lung  tissue,  however,  the  vesicular  murmur  is  harsher 
than  normal.     Usually  the  physical  signs  of  the  disease  are 


oC)  DISEASES  OF   THE  LUNGS 

noted  in  both  lungs.  The  appetite  is  at  times  impaired  or 
absent.  Some  patients,  however,  eat  well.  The  general 
condition  of  the  ])atient  varies  with  the  extent  of  the  lesions. 
In  some  cases  the  dyspnea,  distressing  cough  and  fever 
greatly  debilitate  the  patient,  while  in  others,  especially  in 
horses,  the  general  symptoms  are  not  marked.  It  can 
happen  that  the  catarrhal  pneumonia  is  overlooked  by 
the  owner  and  the  patient  presented  to  the  veterinarian 
only  after  i)uhn()nary  gangrene  or  some  other  termination 
has  set  in. 

Course. — Atypical.  Depends  much  upoli  cause.  Acute 
cases  may  terminate  in  healing  in  two  to  three  weeks. 
Exacerbations,  h()we\er,  are  common  (formation  of  new  foci). 
As  a  rule  catarrhal  pneumonia  takes  a  prolonged  course 
lasting  weeks  or  even  months.  Terminations:  (a)  healing 
in  two  or  three  weeks;  (b)  death  from  asphyxia,  heart  weak- 
ness, exhaustion;  (c)  death  from  pulmonary  gangrene  or 
septicemia  (diarrhea);  (r/)  induration  of  the  lungs  causing 
chronic  dyspnea   ("heaves"). 

Diagnosis. — If  larger  areas  of  the  lung  are  involved,  in 
the  early  stages.it  is  difficult  to  distinguish  catarrhal  from 
fibrinous  pneumonia.  The  following  table  may  be  of  value 
on  this  point: 

Fibrinous  Pneumonia.  Catarrhal  Pneumonia. 

Onset  sudden.  Onset  gradual. 

Course  and  fever  typical.  Course  and  fever  atypical. 

Begins  as  pneunjoiiia.  liegins  with  bronchitis. 

Percussion:    Diffuse  duliiess  over  I'ercussion:      Norniul     or     isolated 

one  lung.  areas  of  dulness  over  both  lungs. 

Auscultation:     Broncliial    l)reath-  Auscniltation:    Rales. 

ing. 

A  benign  disease.  A  malignant  disease. 

From  glanders  (horse)  and  tuberculosis  (ox),  non-specific 
catarrhal  pneumonias  are  now  best  ditt'erentiated  by  the 
use  of  such  scientific  aids  as  the  mallein  (eye)  agglutination, 
complement-fixation,  tuberculin  tests,  etc. 

Treatment. — Place  the  patient  in  a  light,  clean,  and  well- 
ventilated  place.  A])ply  suitable  co\ering  if  the  weather  is 
cold.  (live  good,  easily  digested  food  (clean  oats,  bran 
mash,  bright  hay,  grass,  milk,  eggs,  etc.).     As  there  is  no 


INFLAMMATION  OF  THE  LUNGS  57 

specific,  the  treatment  is  sjTnptomatic  and  follows  that 
outlined  for  fibrinous  pneumonia.  Intratracheal  irrigations 
are  of  little  value  in  catarrhal  pn^eumonia,  unless  applied 
very  early  and  before  the  lung  proper  is  attacked  (washing 
out  the  bronchi)  following  aspiration  of  blood  and  exudate 
after  operations  ("roaring,"  head  sinuses). 

Foreign-body  Pneumonia.  —  Definition.  —  Foreign-body 
pneumonia  is  a  clinical  term  used  to  include  all  forms  of 
inflammation  of  the  lung  due  to  the  entrance  of  coarse 
foreign  matter. 

Etiology. — Foreign-body  pneumonia  is  due  to  the  aspira- 
tion of  dust,  gases,  food,  liquids,  blood,  pus,  etc.  While 
it  occurs  in  all  animals  the  horse  is  the  most  common  victim 
due  to  improper  drenching  and  the  frequency  in  this  animal 
of  pharyngitis,  strangles,  tetanus,  encephalitis  and  purpura 
in  which  diseases  dysphagia  is  a  common  symptom.  The 
dysphagia  following  chloroform  narcosis  and  attending 
forage  poisoning  may  also  lead  to  it.  In  the  ox  the  pharyn- 
geal paralysis  occurring  in  parturient  paresis  is  the  most 
common  etiological  factor,  paunch  contents  being  regurgi- 
tated and  liquid  medicines  unskilfully  given  reaching  the 
windpipe.  Foreign  material  (sharp  objects)  may  also  pene- 
trate the  lung  from  the  reticulum. 

Necropsy. — On  postmortem  it  will  be  noted  that  the 
foreign  material  has  produced  bronchitis  and  areas  of 
bronchopneumonia.  Due  to  the  entrance  of  pus  bacteria 
and  germs  of  putrefaction  there  result  purulent  infiltration, 
necrosis  and  decomposition  of  the  lung  tissue.  Therefore 
gangrene,  abscess  and  putrefaction  are  found  combined 
changing  the  lung  into  a  miscolored,  fetid,  odorous,  smeary 
mass.  By  contact  the  pleura  also  becomes  involved  so 
that  a  purulent  or  putrid  pleuritis  is  present.  More  rarely 
there  may  be  pneumothorax. 

Symptoms. — The  onset  in  foreign-body  pneumonia  is 
usually  insidious  and  may  be  entirely  overlooked  especially 
by  the  owner  or  attendant.  The  disease  begins  as  a  bron- 
chitis and  bronchopneumonia  (cough,  rales).  When  gangrene 
sets  in  the  expirium  has  a  sweetish  odor  which  later  becomes 
fetid.     Soon  nasal  discharge  appears  which  is  discolored  and 


58  DISEASES  OF  THE  LUNGS 

contains  an  admixture  of  lung  tissue  elements.  On  percus- 
sion, dependinff  upon  the  character  and  extent  of  the  lesions, 
there  may  he  flatness,  tympany,  or  even  a  "cracked-pot" 
tone  emitted.  Tlie  ])atient  shows  a  septic  fever  and  rapid, 
weak  pulse  (SO  to  120).  Symptoms  of  plcuritis  (emi)ycma) 
are  not  infrequent.  In  many  cases  the  appetite  remains 
fairly  good  until  the  end  and  the  temperature  may  be 
little  above  normal. 

Diagnosis.  The  diagnosis  depends  upon  the  physical 
signs  of  pneumonia  with  fetid  expirium  and  the  discolored 
nasal  discharge  containing  bits  of  dead  lung  tissue.  A 
microscopic  examination  will  show  elastic  fibers  from  the 
])arenchyma  of  the  lung.  In  all  pneumonias  following 
unskilful  drenching  or  where  dysphagia  exists  foreign- 
body  pneumonia  should  be  suspected.  From  the  stand- 
point of  differential  diagnosis,  diseases  of  the  teeth  and 
sinuses  of  the  head  causing  fetid  breath  must  be  considered. 
An  examination  of  these  parts  and  of  the  lungs  should 
suffice  for  difl'crcntiation.  PVtid  bronchitis,  which  is  most 
common  in  dogs,  does  not  afiect  the  general  condition  of 
the  patient  and  is  rarely  fatal. 

Course  and  Prognosis. — Once  the  disease  is  recognized  the 
course  is  usually  about  one  week.  The  prognosis  is  bad, 
especially  in  horses,  the  disease  leading  to  sapremia  and 
death.  Occasionally  in  cattle  the  gangrenous  mass  remains 
local  in  the  lung  and  becomes  encapsuled  by  connective 
tissue  forming  a  sequester  which  ])n)tects  the  rest  of  the 
organism.     Such  cases  will  heal. 

Treatment. — The  treatment  is  unsatisfactory.  Intra- 
tracheal injections  of  antiseptics  are  of  no  value  except 
in  the  early  stages.  The  treatment  suggested  for  catarrhal 
l)ncuni()nia  is  usually  followed. 

Metastatic  Pneumonia.  Definition. — A  secondary  j)neu- 
monia  the  result  of  embolism. 

Etiology. — Metastatic  ])neumonia  is  the  result  of  a  sj)read 
of  infection  rid  embolism  from  a  ])rimary  focus  containing 
j)us  bacteria,  septic  bacteria  or  necrosis  bacilli  which  reach 
the  lung  through  the  blood.  The  j)rimary  focus  is  usually 
an  abscess  occurring   in    the   course   of  strangles,   purulent 


IXFLAMMATIOX  OF  THE  LUNGS  59 

arthritis,  gangrenous  pododermatitis,  phlegmon  of  the  hind 
limbs,  etc.  It  may  also  result  from  navel  infection  (thrombo- 
phlebitis) of  which  it  is  a  common  sequela  or  it  may  originate 
from  inflammation  of  the  jugular  or  saphenous  veins.  It 
is  a  frequent  sequela  of  acute  gastro-intestinal  disorders  in 
calves. 

Necropsy. — Metastatic  or  embolic  pneumonia  is  charac- 
terized by  multiple  abscess  or  necrotic  centres  which  occur 
throughout  the  lung  tissue.  At  the  same  time  there  are 
svTnptoms  of  septicemia  and  pyemia. 

Symptoms. — The  symptoms  of  metastatic  pneumonia  are 
often  quite  vague,  as  the  embolic  centre  cannot  always 
be  determined  by  percussion  and  auscultation.  Where  a 
primary  abscess  exists,  and  the  patient  suddenly  shows 
septic  fever,  dyspnea  and  cough  a  metastatic  pneumonia 
should  be  thought  of.  In  the  later  stages  s^Tiiptoms  of 
abscess  of  the  lung  (purulent  nasal  discharge,  etc.)  are 
significant. 

Treatment. — Treatment   is   unavailing. 

Interstitial  Pneumonia. — Definition. — Interstitial  pneumo- 
nia is  an  inflammation  of  the  connective  tissue  of  the  lung 
which  proliferates,  causing  induration  or  sclerosis. 

Etiology. — It  is  a  secondary  disease  and  may  follow  any 
form  of  pneumonia,  especially  the  catarrhal.  It  most 
frequently  occurs  in  the  course  of  chronic  pulmonary  tuber- 
culosis, glanders,  contagious  pleuropneumonia  of  cattle, 
verminous  pneumonia  or  any  form  of  inflammation  of  the 
lungs  which  is  chronic. 

Symptoms. — The  symptoms  depend  upon  the  extent  of  the 
connective-tissue  proliferation  and  the  amount  of  infection. 
Briefly,  they  consist  in  dyspnea,  dulness  on  percussion, 
absence  of  the  vesicular  murmur  and  the  gradual  emaciation 
of  the  patient.     There  is  usually  no  increase  in  temperature. 

Diagnosis. — The  diagnosis  of  chronic  interstitial  pneu- 
monia is  extremely  difficult  unless  it  follow  an  acute  attack 
of  croupous  or  catarrhal  pneumonia  or  pleuritis.  In  cattle 
if  due  to  tuberculosis  it  may  be  diagnosed  by  the  tuberculin 
test  and  in  the  horse  the  presence  of  glanders  may  be  deter- 
mined bv  the  various  tests  for  this  disease. 


60  DISEASES  OF  THE  LUNGS 

Course  and  Prognosis. — The  course  is  usually  chroulc,  the 
disease  lasting  for  weeks  or  even  months.  The  prognosis  is 
bad  for,  although  death  may  not  always  ensue,  the  patient 
is  left  with  a  chronic  incurable  dyspnea. 

Treatment. — Treatment  is  of  no  avail.  Life  may  be 
prolonged  by  treating  as  in  catarrhal  ])neumonia.  Edible 
animals  should  be  slaughtered.  In  horses  fibrolysin  (gr.  xv) 
given  subcutaneously  every  other  day  is  recommended. 

TUMORS   IN    THE   LUNG. 

While  tumors  in  the  lung  are  not  uncommon  they  rarely 
attain  clinical  importance,  as  the  diagnosis  is  so  difficult. 
They  sometimes  produce  symptoms  of  dyspnea,  pulmonary 
hemorrhage,  flatness  on  percussion  and  emaciation.  Fever 
is  not  present  and  the  course  is  chronic.  ]\lany  of  them 
originate  by  metastasis.  The  most  common  tumors  are 
sarcomas,  melanomas,  adenomas,  fibromas,  and  in  aged 
animals  particularly  carcinomas. 


CHAPTER  V. 
DISEASES  OF  THE  PLEURA. 

PLEURITIS. 

Definition. — An  inflammation  of  the  pleura.  Pleiiritis  is 
nearly  always  a  secondary  condition  in  animals. 

Occurrence.-^Affects  all  animals  but  principally  the  horse. 
In  the  horse  pleuritis  is  usually  a  symptom  of  infectious 
fibrinous  pneumonia;  in  the  ox  of  tuberculosis,  contagious 
pleuropneumonia  and  hemorrhagic  septicemia,  and  in  swine 
most  frequently  of  so-called  swine  plague.  Pleuritis,  how- 
ever, may  occur  unattended  by  pneumonia,  as  is  frequently 
observed  in  horses. 

Etiology. — Pleuritis  in  animals  is  always  due  to  infection. 
Cold,  which  was  believed  to  be  the  most  potent  etiological 
factor,  is  now  considered  merely  predisposing  (pleuritis  in 
sheep  following  shearing;  exposure  of  horses  to  cold  wind 
and  rain).  The  microorganisms  which  produce  pleuritis  are 
many.  Rarely  is  pleuritis  a  primary  disease — it  is  most 
commonly  seen  in  practice  accompanying  diseases  of  the 
lungs  (pleuropneumonia).  The  microorganisms  causing 
pleuritis  may  enter  as  follows:  (a)  through  penetrating 
thoracic  wounds;  (6)  through  deep  contusions  on  the  chest 
wall,  especially  if  rib  fractures  be  present  (kicks,  blows, 
falls) ;  (c)  from  disease  foci  in  the  lung,  which  are  in  contact 
with  the  pleura;  (d)  via  blood  and  lymph  microorganisms 
of  certain  specific  diseases,  notably  those  which  affect 
principally  the  respiratory  tract,  may  also  invade  the 
pleura  and  cause  inflammation  thereof  (influenza,  fibrinous 
pneumonia,  swine  plague,  hemorrhagic  septicemia,  acute 
rheumatism).  It  may  happen  that  the  dominant  lesions 
are  in  the  pleura,  in  which  case  primary  pleuritis  is  spoken  of 
(pleurisy  of  the  horse  without  pneumonia). 


()2  DISEASES  OF   THE  PLEURA 

As  predisposing  factors  may  l)c  mentioned  refrifi;erati()n 
(cold),  overexertion,  long  railway  transports,  and  acute 
diseases  of  the  respiratory  tract  (laryngitis).  Subacute  and 
chronic  jileuritis  may  accompany  tuberculosis,  glanders, 
contagious  ])leur()pneumonia  of  the  ox,  tumors  (spread  of 
sarcoma  or  carcinoma  via  contiguity  of  tissue,  or  metas- 
tasis, and  animal  parasites  (echinococcus  of  ox,  cysticercus 
tenuicollis  of  sheej),  sclerostomes  in  colts). 

Symptoms. — Depending  ui)on  whether  it  is  acute  or  clironic, 
j)rimary  or  secondary,  the  sym])toms  of  j)leuritis  will  \ary 
greatly.  In  mild  circumscribed  and  in  chronic  pleuritis  the 
symptoms  are  so  vague  that  the  condition  is  rarely  recog- 
nized clinically.  In  the  acute  form,  which  is  at  times 
primary,  they  are  as  follows: 

(a)  First  stage  (congestion):  The  onset  is  sudden.  The 
patient  stops  eating,  seems  stupid,  and  may  show  i)ains 
simulating  mild  colic.  There  is  often  a  marked  chill  during 
which  the  temperature  rises  rapidly  to  104°  to  1()()°  F. 
The  muscles  of  the  thorax  (intercostals)  tremble.  The 
pulse  is  frequent  (70  to  SO),  small  and  hard  ("serous  mem- 
brane pulse")-  The  respirations  are  accelerated  (25  to  40) 
and  of  the  abdominal  type.  If  the  pain  is  great,  and  the 
diaphragm  not  involved,  the  ribs  may  be  rolled  forward 
and  held,  breathing  being  i)erformed  by  the  flanks.  The 
l)atient  may  not  show  cough  or  nasal  discharge. 

Percussing  the  thorax  in  this  stage  ])ains  tiie  patient 
and  causes  coughing.  Sometimes  on  j)alpating  the  inter- 
costal spaces  sensitiveness  is  shown,  especially  in  the  region 
of  the  elbow.  If  the  examiner's  hand  be  laid  against  the 
thorax  a  marked  fremitus  may  be  felt.  I  nless  the  lung  is 
involved  in  this  stage  there  is  no  change  in  the  jxM-cussion 
sound. 

The  rcsj)irations  seem  shorter  than  normal  and  of  an 
interrupted,  catching  character.  On  auscultation  a  rubbing, 
grating,  frictional  sound  is  heard  synchronous  with  the 
resj)irations.  In  rare  instances  the  grating  sound  may  be 
heard  a  distance  from  the  patient.  The  animal  is  usually 
stitt'  and  when  turned  "moves  as  one  piece"  in  a  rigid. 
wooden  fashion. 


PLECRITIS  <)3 

[h)  Second  stage  (effusion):  In  this  stage  the  chnical 
picture  is  a  good  deal  modified.  The  patient  becomes  more 
dyspneic,  and  the  character  of  the  breathing  changed, 
depending  upon  the  quantity  of  exudate  in  the  chest.  If 
a  considerable  amount  of  fluid  forms  rather  rapidly  in  the 
thorax  (25  to  40  liters),  at  inspiration  the  ribs  are  rolled 
forward  ad  maximum  and  at  expiration,  which  is  accom- 
.plished  by  a  double-pumping  movement  of  the  flanks,  the 
lumbar  region  is  elevated  and  the  anus  protruded,  the 
manner  of  performing  the  respirations  much  resembling  that 
noted  in  pulmonary  emphysema.  Along  the  costal  carti- 
lages at  each  expiration  a  groo\-e  is  formed.  The  nostrils 
are  dilated  and  often  flapping.  Percussion:  As  high  up  as 
the  fluid  in  the  chest  extends,  a  marked  flatness  with  resist- 
ance under  the  hammer  is  noted.  The  flat  area  extends 
across  the  ribs  in  a  straight  horizontal  line.  Above  this  line 
subdued  resonance  is  heard.  Changing  the  position  of 
the  body  will  shift  the  horizontal  line.  (Only  feasible  in 
small  animals.)  Auscultation:  When  eft'usion  occurs  the 
frictional  sound  disappears  (in  some  instances  it  may  still 
be  heard  above  the  area  of  flatness),  and,  as  a  rule,  no 
respiratory  sounds  can  be  determined  below  the  horizontal 
line.  Above  it  the  vesicular  murmur  is  harsh;  tubular 
breathing  is  frequently  present. 

The  heart  beat  is  weakened  in  this  stage  and  may  often 
be  heard  more  distinctly  in  the  right  than  on  the  left  side 
of  the  chest.  The  pulse  is  rapid  and  softer  than  in  the 
first  stage.  The  temperature  is  very  irregular.  In  sero- 
fibrinous pleuritis,  when  eft'usion  takes  place,  it  usually 
drops  to  nearly  normal,  but  may  rise  again  later.  Its 
character  is  decidedly  intermittent  or  even  remittent. 
Very  high  fever  speaks  for  purulent  pleuritis.  General 
condition:  In  acute  pleuritis  the  patient  often  remains 
standing  during  the  entire  attack  (horse).  If  the  patient 
lies  down  in  the  first  stage,  due  to  the  pain,  it  rests  on  the 
well  side,  or  if  the  condition  is  bilateral,  on  the  sternum. 
In  the  stage  of  eft'usion,  the  patient  lies  on  the  diseased  side. 
In  pleuritis  there  is  a  tendency  to  edema  on  pendent  portions 
of  the  bodv  (under  chest,  etc.) .  A  total  lack  of  appetite  persists. 


64  DISEASES  OF   THE  PLEURA 

Course. — Mild  cases  make  a  \'ery  rai)id  recovery,  and  are 
often  not  recognized  dnring  life.  The  effusion  forms  rapidly, 
in  three  or  four  days  the  thorax  may  be  half-filled;  the 
resorption  of  the  exudate,  however,  takes  place  gradually 
and  may  require  two  to  three  weeks  or  even  several  months, 
during  which  time  the  life  of  the  patient  is  in  jeopardy. 
The  more  serous  the  effusion,  the  more  likely  and  rapid  the 
resorption.  With  much  fibrinous  exudate  present,  adhesions 
between  lung  and  thoracic  wall  are  frequent.  These  adhe- 
sions usually  persist  and  cause  the  patient  to  be  ever 
afterward  short-winded.  Chronic  pleurites  are  incurable. 
Death  in  acute  cases  may  follow  from  asphyxia  or  exhaustion 
in  two  or  three  weeks. 

Diagnosis. — The  pathognomonic  symptom  of  pleiu-itis  is 
the  frictional  (rubbing)  sound  on  auscultation.  A  sensitive- 
ness of  the  intercostal  spaces  occurring  in  a  disease  (pneu- 
monia) which  pleuritis  is  apt  to  follow  is  significant.  In 
the  second  stage  the  horizontal  line,  limiting  dorsally  the 
extremely  flat  i)ercussion  sound,  is  characteristic.  In  pleuri- 
tis the  onset  is  usually  different  from  fibrinous  pneumonia. 
In  the  latter  the  pulse  is  full,  the  conjunctiva  congested 
(often  mahogany-colored),  there  is  a  rusty-brown  nasal 
discharge  and  the  area  of  dulness  on  percussion  is  not  so 
flat  and  resistant  under  the  hammer.  In  pleuritis  marked 
dyspnea  is  an  early  symptom,  the  i)ulse  is  hard  and  small 
(wiry)  and  on  palpation  muscular  tremors  o\'er  the  region 
of  the  thorax  are  felt.  Pneumonia  is  usually  unilateral, 
]jleuritis  bilateral.  Cough  is  much  more  easily  induced  in 
l)neumonia  than  in  pleuritis.  The  temperature  is  high 
usually  only  in  the  beginning  of  pleuritis;  in  pneumonia  the 
fever  is  of  the  continuous  type  and  lasts  five  to  nine  days, 
to  fall  by  crisis.  In  cases  complicated  with  pneumonia 
the  recognition  of  the  pleuritis  may  be  difficult.  Weakening 
of  the  heart  sountls  and  edema  of  the  ventral  part  of  the 
thorax  are  significant.  In  doubtful  cases  the  use  of  the 
exploring  needle  to  determine  whether  effusion  is  present 
or  not  is  advisable.  By  drawing  oW  some  of  the  fluid  and 
subjecting  it  to  chemical  (albumin),  microscopic  (pus  cells, 
specific  bacteria),  and  bacteriological  examination  (inocula- 
tion of  animals)  the  form  of  pleuritis  may  be  determined. 


PLEURITIS  ()5 

Prognosis. — Should  he  guartled.  In  fihrinous  forms  com- 
phcating  pneumonia  the  outlook  is  usually  good.  With 
great  effusion  affecting  seriously  the  pulse,  respirations  and 
appetite,  the  prognosis  is  bad.  If  pus  infection  occur, 
death  may  be  looked  for.  In  pleuritis  relapses  are  common. 
In  cases  which  do  recover  from  the  prolonged  acute  attack, 
"heaves"  (adhesions)  is  a  common  sequela. 

Treatment. — The  hygienic  and  dietetic  treatment  is  the 
same  as  in  pneinnonia.  Local  applications  to  the  chest, 
especially  cold  water  in  the  early  stage  (first  two  or  three 
days,  when  friction  sound  is  heard),  are  good.  When  effu- 
sion is  developed,  hot  applications  (blankets  wrung  out  in 
hot  water)  are  better.  In  protracted  cases  or  in  chronic 
pleuritis,  employ  sharp  blisters  (spirits  of  mustard). 

Drugs. — If  there  is  acute  pain  (sensitiveness  of  inter- 
costal spaces,  marked  stiffness  on  turning  the  patient),  or  in 
distressing  cough,  morphin  (gr.  v)  or  tincture  of  opium 
(3iij)  may  be  given.  When  eft'usion  forms,  diuretics  and 
physics  assist  in  the  elimination  of  the  fluid.  Calomel 
(5j)  and  aloes  (5vj)  are  given.  Small  repeated  doses  of  the 
fluidextract  of  digitalis  (5j)  so  often  recommended,  should 
be  administered  with  caution,  watching  its  effect  on  the 
appetite  and  heart.  Acetate  of  potash  (§j),  pilocarpin  (gr. 
iv),  arecalin  (gr.  j),  and  eserin  (gr.  j)  should  be  used  only 
when  the  heart  is  not  too  weak. 

If  the  quantity  of  effusion  warrant  (dyspnea)  puncture 
of  the  thorax  should  be  practised  at  once.  If  thoracentesis 
is  properly  performed  it  is  not  dangerous.  The  operation 
is  simple:  In  the  seventh  intercostal  space,  close  to  the 
anterior  margin  of  the  rib,  and  about  1  inch  above  the 
union  of  the  cartilage  and  rib,  shave,  disinfect,  and  puncture 
the  chest  with  a  small  sterile  trocar.  It  is  recommendable 
to  first  cut  through  the  skin  with  a  bistoury  and  draw  the 
incision  to  one  side  that  the  skin  and  muscle  wounds  do  not 
cover  each  other  when  the  puncturing  instrument  is  with- 
drawn. Care  should  be  taken  to  prevent  air  entering  the 
thorax  during  the  operation.  The  fluid  should  be  removed 
slowly  and  if  the  dyspnea  become  worse,  coughing  induced 
or  the  pulse  become  weak,  the  cannula  should  be  instantly 
5 


66  DISEASES  OF   THE  PLKVRA 

withdrawn  and  the  opening  covered  with  tar  or  coHodion. 
Thoracentesis  should  be  performed  early  and  rei)eatcdly  to 
be  of  curative  value. 


HYDROTHORAX. 

Definition. — A  collection  of  transudate  in  the  chest  not 
due  to  an  inflammation  of  the  pleura. 

Etiology. — In  a  general  way  hydrothorax  is  due  to  a 
congestion  in  the  vena  cavte  or  its  tributaries.  It  is  most 
commonly  noted  in  chronic  heart,  lung  and  kidney  diseases 
and  is  usually  associated  with  ascites,  anasarca,  and  hydro- 
pericardium. 

It  may  also  accompany  general  anemia,  hydremia  and 
prolonged  cachectic  conditions  following  parasitism,  carcino- 
matosis, etc. 

Symptoms. — Same  as  the  effusion  stage  in  serofibrinous 
plcuritis. 

Diagnosis. — History,  finding  organ  primarily  attacked 
(heart,  lung,  kidneys)  and  the  prolonged,  feverless  course 
generally  suffice  to  secure  a  diagnosis.  In  doubtful  cases, 
the  thorax  may  be  tai)ped  i\m\  fluid  withdrawn  and  examined. 
It  is  usually  much  clearer,  less  fiocculent  and  more  watery 
than  pleural  exudate.  It  is  straw-yellow  in  color  and  has 
a  specific  gravity  of  lOK),  the  albumin  content  below  2  per 
cent.     Leukocytes  are  only  sparingly  represented. 

Treatment. — As  the  j)rimary  condition  is  usually  incur- 
able, little  can  be  done  in  hydrothorax.  In  great  dyspnea, 
thoracentesis  will  afford  relief. 

PNEUMOTHORAX. 

Definition. — The  entrance  of  air  into  the  i)lcural  .sacs.  It 
is  rarely  due  to  other  gases. 

Etiology. — («)  Penetrating  wounds  through  the  outer 
wall  of  the  chest  or  through  the  diaphragm  (from  the  retic- 
ulum). (//)  Rupture  of  the  esophagus  from  the  rough  use 
of  the  ])rol)ang.  {(•)  Abscesses  or  gangrenous  foci  in  the 
lungs  which   rui)turc,  opening  bronchi   into  communication 


PNEUMOrilORAX  67 

with  the  pleural  sacs,  (d)  In  rare  instances  rupture  of  the 
lung  may  be  a  cause. 

Symptoms. — Severe  dyspnea,  which  develops  usually 
rapidly  and  may  lead  to  death  in  twenty-four  hours  (pul- 
monary collapse),  or  from  the  microorganisms  carried  in  by 
the  air  a  purulent  pleuritis  (empyema)  develops.  The 
sound  on  percussion  has  a  peculiar  metallic  ring  which  is 
usually  heard  over  the  whole  chest.  Pleuritis  develops  in 
most  cases  which  modifies  the  percussion  sound.  On  auscul- 
tation often  no  sounds  are  audible.  If  fluid  is  present 
metallic  gurgling  sounds  are  heard. 

Diagnosis. — Usually  not  difficult  in  veterinary  patients, 
as  most  cases  are  due  to  penetrating  chest  wounds. 

Course  and  Prognosis. — Usually  leads  to  pleuritis  and 
death.  Cases  not  due  to  wound  infection,  such  as  may 
follow  rupture  of  the  lung,  can  recover. 

Treatment. — In  human  practice  the  air  is  pumped  out  of 
the  pleural  sacs  by  a  special  apparatus.  Seldom  useful  in 
veterinary  practice. 


PART  II. 
DISEASES  OF  THE  CIRCDLATORY  ORGANS. 


CHAPTER   I. 
DISEASES  OF  THE  HEART  SAC. 

PERICARDITIS. 

Definition. — An  inflammation  of  the  heart  sac. 

Occurrence. — It  is  usually  secondary  in  animals,  associated 
with  such  diseases  as  pleuropneumonia  in  the  horse  and  the 
pleuropneumonia  in  hog  cholera.  In  the  ox  pericarditis 
usually  results  from  direct  injury  by  foreign  bodies  which 
pass  from  the  reticulum  or  rumen  (traumatic  pericarditis), 
or  it  may  be  due  to  tuberculosis. 

Etiology. — Infection.  Most  of  the  pathogenic  micro- 
organisms affecting  animals  are  capable  of  producing  peri- 
carditis. In  practice,  therefore,  it  occurs  concomitant  with 
many  infectious  diseases  (tuberculosis,  influenza,  hog 
cholera,  hemorrhagic  septicemia).  The  most  common  and 
important  form  of  this  disease  seen  in  animals  is  the  traumatic 
pericarditis  of  the  ox.  The  frequency  with  which  foreign 
objects  (needles,  wire,  etc.)  are  found  in  the  reticulum,  to 
which  attention  is  drawn  in  dealing  with  the  diseases  of  the 
digestive  tract,  the  close  proximity  of  the  reticulum  to  the 
pericardium,  and  the  marked  contractions  of  this  com- 
partment of  the  stomach,  are  the  most  important  factors 
in  the  etiology  of  this  common  condition.  In  other  animals 
(horse,  swine,  sheep)  traumatic  pericarditis  only  occasionally 
occurs. 


70  DISEASES  OF   THE  HEART  SAC 

Symptoms. — In  traumatic  pericarditis  of  the  ox,  tlie 
heart  symptoms  are  usually  ])rece(le(l  by  those  of  traumatic 
indigestion  (see  this),  hupiiry  therefore  should  always  he 
made  into  the  past  history  of  the  patient  in  thi.s  regard. 
The  cardinal  sym])t()ms  are  as  follows:  (d)  In  the  early 
stages  stiffness  and  disinclination  to  move.  The  i)atient 
remains  down  most  of  the  time,  (b)  Dyspnea  when  the 
patient  is  forced  to  exercise,  the  al)dominal  type  of  respira- 
tion predominating,  (r)  The  pulse  is  rapid  and  irregular. 
(d)  A  pronounced  undulation  in  the  jugulars  (venous  i)ulse) 
is  seen,  (e)  Later  edematous  swellings  appear  under  the 
throat,  neck,  brisket,  and  chest.  (/)  Percussion  is  usually 
painful,  the  animal  wincing  and  grunting  when  the  chest 
is  struck  over  the  heart  region.  An  increased  area  of  cardiac 
dulness  may  be  determined  in  cattle  if  not  too  fat.  {(/)  On 
auscultation,  provided  no  efi'usion  has  taken  place,  a  friction 
tone  like  that  heard  in  pleuritis  but  synchronous  with  the 
heart  beat  is  heard.  If  the  heart  sac  is  filled  with  fluid 
and  gas,  metallic  tinkling  tones  modify  the  normal  heart 
sounds  which  are  muffled  and  distant.  (//)  The  patient 
usually  shows  rise  in  temperature,  but  the  fever  is  generaly 
mild  and  atypical.  Not  infrequently  the  clinical  symptoms 
of  traumatic  pericarditis  are  entirely  overlooked,  the  first 
intimation  of  any  trouble  appearing  when  the  patient 
drops  over  dead.  The  general  condition  of  the  patient 
due  to  the  loss  of  appetite  and  attending  infection  or  intoxi- 
cation (septicemia,  sapremia)  grows  bad.  The  patient 
emaciates,  becomes  anemic,  weak,  and  may  suffer  from 
diarrhea. 

Course  and  Prognosis. — The  course  in  traumatic  peri- 
carditis is  usually  a  prolonged  one,  the  condition  lasting 
often  several  weeks  or  even  months.  Exjicerbations  and 
remissions  are  very  common.  As  a  general  rule,  however, 
there  is  a  slow  but  steady  decline.  Metastases  are  not 
uncommon,  the  disease  assuming  the  form  of  a  pyemia, 
leading  to  enlargement  of  the  joints,  lameness,  etc.  Pneu- 
monia and  ])leurisy,  and  gastro-intestinal  catarrh  are  frequent 
comi)licati()ns.  Death  may  occur  at  any  time  during  the 
disease  from  the  foreign  body  penetrating  the  heart  nuiscle 


HYDROPERICARDIUM  71 

or  from  injury  to  the  coronary  bloodvessels  causing  fatal 
hemorrhage.  The  patient  may  also  die  from  the  attending 
sapremia.  Occasionally  cases  occur  in  which  great  improve- 
ment in  the  condition  is  noted,  the  patient  gaining  in  .flesh, 
appetite,  and  strength.  Usually,  howe\'er,  the  improvement 
is  only  temporary.  Rarer  still  are  those  instances  where  a 
spontaneous  recovery  follows  the  escape  of  the  foreign 
body  through  an  abscess  to  the  outside  world. 

Diagnosis. — While  in  typical  and  advanced  cases  the  diag- 
nosis is  easy,  traumatic  pericarditis  in  the  earlier  stage  may 
be  exceedingly  difficult  to  recognize.  Eber  recommends, 
where  the  condition  is  suspected  and  fever  exists,  to  give 
acetanilid  (Siij)  daily,  which  reduces  the  temperature  but 
not  the  pulse  which  remains  high  (100  to  120)  if  pericar- 
ditis is  present.  In  doubtful  cases  an  explorative  puncture 
of  the  pericardium  will  determine  the  presence  of  fluid. 

Treatment. — As  nearly  all  cases  are  fatal,  the  immediate 
slaughter  of  the  animal  is  recommended.  In  very  valuable 
pregnant  animals  an  eft'ort  to  prolong  life  may  be  made  by 
the  use  of  such  drugs  as  digitalis  (5ss);  caffein  (5j),  or  oil 
of  camphor  (3j)  subcutaneously.  Stimulants  (alcohol  and 
ether)  are  also  in  order.  In  Europe  puncturing  the  peri- 
cardium with  a  trocar  has  been  employed. 


HYDROPERICARDIUM. 

Definition. — A  filling  of  the  heart  sac  with  transudate  not 
due  to  a  pericarditis. 

Etiology. — Usually  is  associated  with  hydrothorax,  ascites, 
and  anasarca.  It  may  be  secondary  to  chronic  heart,  lung, 
liver,  and  kidney  diseases,  or  diseases  of  the  blood,  as 
hydremia,  anemia,  the  cachexia  of  chronic  parasitism,  and 
the  last  stages  of  chronic  infectious  diseases  (glanders, 
tuberculosis). 

Symptoms. — First,  those  of  the  primary  disease  followed 
by  general  dropsy  which  involves  the  heart  sac.  The 
area  of  cardiac  dulness  is  enlarged,  heart  tones  weak,  pulse 
weak,  edema  of  the  skin,  dyspnea,  and  albuminuria. 


72  DISEASES  OF   THE  HEART  SAC 

Diagnosis. — Similar  to  acute  pericarditis  except  that  acute 
iiiHanimatory  symptoms  (fever,  pain,  etc.)  fail. 

Treatment. — Generally  of  little  value,  as  the  primary  dis- 
ease cannot  be  eradicated.  Diuretics  and  diaphoretics 
(pilocarpin)  are  indicated.  Tapping  the  pericardium  may 
be  tried. 

PNEUMOPERICARDIUM. 

Definition. — Gas  in  the  heart  sac. 

Occurrence. — Rarely  met  with  except  in  tramatic  pericar- 
ditis of  the  ox. 

Etiology. — Due  to  gas  forming  in  the  putrid  exudate  con- 
tained in  the  pericardium,  the  result  of  sharp-pointed 
foreign  bodies,  which  come  from  the  reticulum,  penetrating 
the  organ.  Rarely  occurs  from  penetrating  thoracic  wounds 
involving  the  heart  sac. 

Symptoms. — Like  those  noted  under  traumatic  pericarditis: 
Dyspnea;  on  percussion  increased  area  of  cardiac  dulness. 
Auscultation:  Metallic  tinkling  sounds— heart  beat  muffled 
and  distant.  In  some  cases  splashing  sounds  resembling 
those  of  a  water  wheel  may  be  heard  a  distance  from  the 
patient. 

Prognosis. — Bad.     Healing  rare. 

Treatment. — See  Traumatic  Pericarditis. 

HEMOPERICARDIUM. 

Definition. — Collection  of  blocnl  in  the  heart  sac.  The 
blood  conies  from  either  the  heart  cavities,  coronary  blood- 
vessels, aortic  or  pulmonary  trunk. 

Etiology. — Spontaneous  rupture  or  injury  of  the  heart, 
coronary  vessels,  aortic  or  pulmonary  trunks. 

Symptoms. — In  most  instances  leads  to  death  in  a  few 
minutes.  Only  in  those  cases  where  the  hemorrhage  devel- 
oped slowly  would  the  patient  survive  long  enough  for 
clinical  symptoms  to  appear.  In  such  cases  the  symptoms 
are  those  of  filling  of  the  pericardium,  pale  mucous  mem- 
l)ranes,  ])rofuse  sweating,  dyspnea,  rai)id,  irregular,  feeble 
l)ulse,  uneasiness  and  finally  death. 


CHAPTER   11. 
DISEASES  OF  THE  HEART. 

NERVOUS    PALPITATION    OF    THE    HEART. 

Hyperkinesis  Cordis. 

Definition. — A  sudden,  tumultuous  beating  of  the  heart  of 
purely  nervous  origin,  and  independent  of  any  lesions  in  the 
organ.  ^ 

Occurrence. — Not  common  in  animals,  but  may  occur  in 
highly  nervous  horses. 

Etiology. — Nervous  palpitation  may  result  from  over- 
exertion, great  fear  (stable  fires),  or  anything  which  produces 
undue  excitement.  It  may  be  secondary  to  mild  gastric 
indigestion  and  occur  in  anemic  conditions,  or  may  follow 
influenza. 

Symptoms. — The  characteristic  symptom  of  this  disorder 
is  a  thumping  movement  of  the  thorax  which  may  be  seen, 
felt  or  heard.  The  patient  is  usually  anxious,  sweating 
copiously  and  somewhat  dyspneic.  On  auscultation  the 
heart  beiat  is  loud  and  fkst,  often  at  each  impulse  jarring 
the  whole  body.     The  pulse  may  be  quite  weak. 

Course. — Acute,  lasts  in  most  cases  only  a  few  hours  to 
one  day. 

Diagnosis. — Absence  of  organic  heart  disease  and  short 
duration  of  the  condition  are  indicative. 

Treatment. — Patient  should  be  kept  quiet  and  in  a  cool 
place.  Moderate  walking  exercise  is  helpful.  Internally 
chloral  hydrate  (5j),  morphin  (gr.  v),  or  bromides  (Bss) 
may  be  given. 

1  Most  cases  described  under  palpitation  of  the  heart  are  undoulitedly 
due  to  («)  spasm  of  the  diaphragm;  (/))  organic  heart  disease. 


74  DISEASE.'<  OF   THE  HEART 

SLOW  HEART  BEAT.     BRADYCARDIA. 

Definition. — The  frequency  of  the  heart  beat  is  less  than 
normal. 

Etiology. — P^rom  a  i)hysiolofjical  standpoint  it  is  due  to  a 
stinuilation  of  the  vagus  nerve  from  diseases  of  the  brain 
afiecting  course  of  vagus,  or  reflexly  from  gastro-intestinal 
disorders.  Disease  of  the  heart  (degeneration,  atrophy, 
myocarditis)  may  also  induce  it.  Often  the  cause  cannot 
be  determined. 

Symptoms. — The  pulse  is  too  slow.  In  the  horse  it  may 
be  in  extreme  cases  only  9-12-20  per  minute.  The  force 
of  the  beat  is  normal  and  the  condition  of  the  patient  good. 

Diagnosis. — To  determine  whether  bradycardia  is  due  to 
an  irritated  vagus  or  to  some  lesion  of  the  heart  itself, 
sulphate  of  atropin  (gr.  I)  may  be  injected  subcutaneously. 
If  from  the  vagus  it  will  temporarily  disappear  after  giving 
the  atropin. 

Treatment. — Excitants  (alcohol,  ether,  atrojjin)  may  be 
tried  if  the  condition  ])roduces  symptoms  of  heart  weakness, 
languor,  stupor,  or  nervous  symptoms  (convulsions). 

INTERMITTENT    HEART    BEAT. 

Arhythmia  Cordis. 

Definition. — A  condition  in  which  one  or  more  heart  beats 
are  omitted. 

Etiology. — An  intermittency  of  the  heart  is  quite  common 
in  horses.  It  may  exist  for  some  weeks  and  disapjiear 
spontaneously.  On  exercise  the  symptom  may  temporarily 
disa])pear.  Common  causes  are:  (a)  Brain  diseases  afl'ect- 
ingthe  \'agus  (liydro('ei)lialus,  tumor,  cerebritis);  (b)  digestive 
disorders  (constipation,  catarrh);  (r)  diseases  of  the  heart 
itself  (myocarditis,  endocarditis). 

Symptoms. — One  or  more  heart  beats  are  dropped.  It 
may  be  e\-ery  fourth,  sixth  or  eighth  beat  and  occur  with 
great  regularity.  I'suall\'  the  beat  following  the  i)ause  is 
louder  than  the  others.     It  may  happen  that   two  beats 


HYPERTROPHY  AND  DILATATION  OF    THE  HEART     75 

together  are  dropped.  Occasionally,  two  beats  occur  in 
rapid  succession  followed  by  a  long  pause.  In  some  cases 
exercise  emphasizes  the  condition,  in  others  it  temporarily 
relieves  it. 

Course. — If  due  to  some  acute  disease  which  it  accompanies, 
it  will  disappear  with  the  healing  of  the  disease.  In  some 
cases  it  remains  during  the  life  of  the  patient,  but  never 
causes  disorder. 

Treatment. — If  secondary  the  disease  which  it  accompanies 
must  first  be  eradicated  (gastric  disorders).  Usually  no 
treatment  is  demanded  in  idiopathic  cases. 

HYPERTROPHY    AND    DILATATION    OF    THE    HEART. 

Definition. — Hypertrophy  is  an  enlargement  of  the  heart 
due  to  a  thickening  of  its  musculature.  Dilatation  is  an 
enlargement  of  the  heart  due  to  an  increase  in  the  size  of  its 
cavities.     The  two  conditions  usually  coexist. 

Etiology. — A  pathological  hypertrophy  of  the  heart  may 
be  due  to  anything  which  interferes  with  the  heart  action 
from  without:  as  an  adhesion  of  the  pericardium  to  the 
heart;  chronic  lung,  liver  and  kidney  diseases,  in  that  they 
increase  the  heart's  work  by  resisting  the  free  flow^  of  blood ; 
or  from  within,  as  a  valvular  lesion.  Generally  the  hyper- 
trophy is  confined  to  one  chamber,  although  all  may  be 
involved.  When  the  heart  has  increased  sufficiently  in  size 
and  strength  to  overcome  the  obstacle,  the  free  circulation 
is  restored  and  the  hypertrophy  is  spoken  of  as  compensator}'. 
In  case  the  hypertrophy  cannot  overcome  the  obstacle,  dila- 
tation wall  result. 

Symptoms. — A  compensatory  hypertrophy  may  not  cause 
any  symptoms.  In  hypertrophy  with  dilatation  the  symp- 
toms are  as  follows:  The  owner  is  attracted  by  the  dyspnea 
which  develops  during  work.  In  some  instances  the  patient 
may  have  occasional  attacks  of  vertigo  or  palpitations 
("thumps")  when  exercised.  Undulation  of  the  jugulars  is 
sometimes  noted.  In  the  latter  stages  edema  appears 
under  the  chest.     The  pulse^  is  weak  and  arhythmic.     Per- 

'  In  hypertrophy  without  dihitatioii,  the  pulse  is  full  iind  quite  strong;. 


76  DISEASES  OF   THE  HEART 

cussion:  The  area  of  cardiac  dulness  is  increased,  extending 
back  as  far  as  the  7th  rib;  it  may  extend  upwardly  to  the 
height  of  the  shoulder-joint.  Auscultation:  The  heart 
beat  is  stronger  and  louder  than  normal.  In  some  cases  it 
may  shake  the  whole  body  (palpitation).  In  the  last  stages 
general  dropsy  usually  sets  in. 

Course. — Acute  cases  of  dilatation  often  recover  if  properly 
treated.  As  a  rule,  however,  the  condition,  coexisting  with 
hypertrophy,  becomes  chronic  leading  to  general  dropsy  and 
death.  In  advanced  cases  any  unusual  exertion  (hard 
pulling,  racing)  may  result  in  the  patient  falling  dead  in 
harness. 

Diagnosis. — Increase  in  extent  of  cardiac  dulness,  abnor- 
mally loud  systolic  tone,  weak  arhythmic  pulse  and  tendency 
to  dropsical  swellings  are  indicative  of  dilatation.  A  hard, 
full  pulse  with  increased  area  of  cardiac  dulness  on  percus- 
sion, speaks  for  hypertrophy.  From  })ericar(litis  the  con- 
dition may  be  differentiated  by  the  weakness  of  tlie  heart 
tone  and  the  frictional  l)ruit  in  this  disease.  From  hydro- 
pericardium  by  the  absence  of  the  gurgling  or  metallic  tinkling 
sounds  on  auscultation. 

Treatment. — Healing  only  possible  in  acute  cases  of 
dilatation.  Allowing  the  patient  absolute  rest  and  giving 
cardiac  tonics,  especially  digitalis  fluidextract  (3ss)  to 
which  strychnin  nitrate  (gr.  j)  may  be  added  are  helpful. 
The  patient  should  be  well  cared  for  and  fed  highly  mitritious 
food. 

MYOCARDITIS. 

Definition. — An  inflammation  of  the  heart  muscle. 

Etiology. — ^Myocarditis  in  animals  is  usually  of  infectious 
origin.  In  practice  it  is  seen  to  accompany  influenza, 
septicemia  and  foot-and-mouth  disease.  Cases  occasionally 
occur  in  azoturia  or  may  follow  ovcirexertion  or  heatstroke. 
In  cattle  foreign  bodies  penetrating  the  heart  muscle  form 
a  cause.  Myocarditis  may  further  be  secondary  to  endocar- 
ditis and  pericarditis.  In  man  myocarditis  connnonly  results 
from  arteriosclerosis  which  in  animals  is  extremely  rare. 

I^'roni  a  pathological  standpoint  three  forms  of  myocar- 


ENDOCARDITIS  77 

ditis  may    be    distinguished:    (a)    Acute    parenchymatous, 
(6)   chronic  interstitial,  and  (c)  purulent  (heart   abscess). 

(a)  The  acute  parenchymatous  form  involves  the  muscle 
fibers  of  the  heart.  ]\Iacroscopically,  the  heart  appears  often 
striped  or  spotted  (tiger  heart),  is  of  friable  consistency 
and  lighter  color  than  normal. 

(b)  The  chronic  interstitial  myocarditis  involves  the  inter- 
muscular connective  tissue  which  proliferates,  leading  in 
many  cases  to  a  thinning  from  atrophy  of  the  heart  muscle 
with  occasional  local  distention  of  the  cavities  (heart 
aneurysm). 

(c)  Abscess  of  the  heart  is  usually  seen  in  traumatic 
myocarditis  of  cattle  and  in  pyemia.  The  musculature 
of  the  heart  will  contain  a  number  of  pea-  to  walnut-sized 
abscesses,  or  in  some  cases  small,  multiple,  miliary  pus 
centres. 

Symptoms.- — Acute  myocarditis  begins  suddenly  with 
symptoms  of  heart  weakness  (palpitation,  very  rapid 
pulse,  dyspnea).  Death  may  be  apoplectic,  due  to  heart 
paralysis.  Clinically,  it  is  extremely  difficult  to  distinguish 
between  myocarditis  and  acute  dilatation  of  the  heart,  or 
the  parenchymatous  degenerations  so  common  in  febrile 
disorders.  During  life  myocarditis  is  usually  not  diagnos- 
able  in  animals.  P'rom  pericarditis  and  endocarditis  it 
may  be  distinguished  by  the  absence  of  the  characteristic 
bruits  of  these  conditions. 

Treatment. — Heart  stimulants  especially  injections  of  oil  of 
camphor  (5iij),  or  caffein  (5  j),  or  veratrin  are  recommended. 

ENDOCARDITIS. 

Definition. — An  inflammation  of  the  endocardium  which 
may  be  (a)  acute  or  (6)  chronic. 

Acute  Endocarditis. — Acute  endocarditis  is  usually  of 
infectious  or  hematogenous  origin.  It  may  therefore  be 
due  to  several  different  microorganisms.  In  animals  it  is 
usually  caused  by  the  bacteria  of  septicemia  and  pyemia. 
The  streptococci,  staphylococci,  and  varieties  of  the  colon 
bacillus,  which  have  entered  the  blood  in  puerperal  septicemia 


7S  DISEASES  OF   THE   HEART 

and  pyemia  of  the  ox  or  wound  infection  in  the  horse,  are 
common  causes. 

Secondarily  acute  endocarditis  may  occur  as  a  symptom 
of  various  infectious  diseases  (erysipelas  of  swine,  influenza 
of  the  horse,  articular  rheumatism  of  cattle).  Endocarditis 
the  result  of  refrigeration,  traumatism  or  from  a  spreading 
of  the  inflammation  of  pericarditis  or  myocarditis  is  rare. 

Pathologically  two  forms  of  acute  endocarditis  are  dis- 
tinguished :  (a)  verrucous,  {h)  ulcerous.  These  forms,  how- 
ever, are  frequently  combined. 

The  verrucous  form  leads  to  organized  exudate  forming 
on  the  margins  of  the  valves,  so-called  vegetation,  which  leads 
to  thickening,  distortion  and  adhesions,  rendering  the  valve 
inefficient.  The  ulcerous  endocarditis  is  a  necrotic  inflam- 
mation of  the  endocardium  with  the  development  of  pea-  to 
hickory  nut-sized  ulcers.  These  are  usually  the  result  .of 
metastasis  (lungs,  kidneys), 

Symptoms. — The  symptoms  are  heart  palpitation  and  very 
rapid,  weak,  often  imperceptible,  irregular,  intermittent 
l)ulse  (horses  80  to  KiO).  In  rare  instances  the  heart  beat 
is  twice  as  fast  as  the  pulse.  There  is  dyspnea  and  high 
fever  (104°  to  105°  F.).  Characteristic  of  the  condition 
are  the  systolic  or  diastolic  bruits  which  occur,  depending 
ui)()n  which  valves  or  openings  are  involved.  AMien  of 
metastatic  origin  there  may  be  brain  (apoplexy),  lung 
(asphyxia),  kidney  (hematuria),  or  limb  (lameness)  symp- 
toms. 

The  course  is  either  peracute,  causing  death  in  a  few 
hours,  or  acute,  ending  fatally  in  a  few  weeks;  or  more  rarely 
the  course  is  chronic,  leading  to  chronic  \ahular  disease  of 
the  heart. 

Differential  Diagnosis. — The  condition  may  be  confused 
with  a  number  of  acute  disorders  such  as  pulmonary  edema, 
l)neumonia  (dyspnea),  sej)ticemia  and  i)uerperal  fever.  If 
the  characteristic  bruits  an*  absent  a  diagnosis  may  be 
impossible. 

Treatment. — Consists  in  (piiet  and  cold  api)lications  to 
the  chest.  Tlcerous  endocarditis  is  usually  incurable. 
The   verrucous   form,    however,    is   more    benign.     Hecom- 


ENDOCARDITIS  79 

mendahle  are  digitalis  (oiv)  followed  by  strophanthus  (oj)- 
Heart  weakness  may  best  be  comliated  by  subcutaneous 
injections  of  oil  of  camphor.  Where  fever  is  present, 
acetanilid  (5i)  or  salicylate  of  soda  (5j  to  ij)  may  be  tried. 

Chronic  Endocarditis. — Etiology. — This  condition  which 
occurs  in  dogs,  horses,  swine  and  cattle  in  the  order  named 
usually  follows  acute  endocarditis  (septicemia,  articular 
rheumatism  of  cattle,  influenza  of  horses,  erysipelas  of 
swine  and  hog  cholera).  Otherwise  the  disorder  may 
develop  gradually  following  the  abuse  of  the  heart  (over- 
exertion, refrigeration,  psychic  influence).  In  animals  it  is 
rarely  due  to  arteriosclerosis.  In  rare  instances  valvular 
troubles  may  be  congenital  (defects  in  the  valves,  oval 
foramen,  or  septum).  Tumors  leading  to  stenosis  of  the  ostia 
are  rare  causes. 

Pathologically  valvular  troubles  lead  either  to  insufficiency 
or  stenosis  of  the  valve  or  ostium  concerned.  Commonly 
these  are  combined. 

General  Symptoms. — The  clinical  features  of  valvular 
disease  may  be  divided  into  two  stages:  (a)  The  stage  of 
compensation,  and  (6)  the  stage  of  disturbance  in  compen- 
sation. 

(a)  From  a  resulting  compensatory  hypertrophy  the 
trouble  with  the  valve  may  be  for  a  long  time  overcome. 
Clinically,  no  symptoms  exist  other  than  either  a  systolic 
or  diastolic  murmur  with  hypertrophy  of  the  left  or  right 
heart.  The  general  condition  and  efficiency  of  the  patient 
is  not  much  disturbed. 

(6)  In  the  stage  of  disturbance  in  compensation  the 
compensatory  hypertrophy  has  been  partially  or  totally 
overcome.  Dilatation  displaces  hypertrophy.  This  induces 
symptoms  of  heart  weakness  (increased,  weak,  inequal, 
irregular  pulse),  congestion  of  the  lungs  (dyspnea),  conges- 
tion of  the  mucous  membranes  and  the  skin  (cyanosis), 
undulation  of  the  peripheral  veins  (venous  pulse),  irregu- 
larity of  the  heart  (vertigo),  congestion  of  the  kidneys 
(albuminuria),  and  in  general  to  cardiac  hydropsy  (anasarca, 
ascites,  hydrothorax,  hydropericardium),  as  well  as  anemia, 
emaciation,  and  weakness. 


80  DISEASES   or   Till':   HEART 

ItidnidiKil  \'(ilciil(ir  and  OsiUd  Defects. — (a)  Mitnil 
insufficiency,  most  common  in  the  horse,  dog  and  swine 
(left  heart).  SystoHc  bruits  very  loud;  accentuated  second 
heart  tone.     Pulse  normal  to  weaker. 

(6)  Mitral  stenosis:     Diastolic  bruits,  weak  pulse. 

(r)  Tricuspid  insufficiency:  Most  common  valvular 
trouble  of  cattle  {y\^\\X  heart).  Systolic  bruits,  venous 
pulse,  cyanosis. 

{d)  Tricuspid  stenosis:  Diastolic  bruits,  venous  pulse  in 
the  ox. 

(e)  Aortic  insufficiency:  Diastolic  bruits.  Pulsation  at 
base  of  neck;  peculiar  swishing  sound  on  auscultation. 
Sometimes  fremitus  mav  be  felt.  Pulse  strong  and  rapid. 
(P.  celer.) 

(/)  Aortal  stenosis:  Systolic  bruits  with  a  very  small, 
slow  pulse  in  horse  and  dog.     Vertigo  from  brain  anemia. 

ig)  Pulmonary  insufficiency:    Diastolic  bruits  (very  rare). 

ill)  Pulmonary  stenosis:    Systolic  bruits  (very  rare). 

Treatment. — Treatment  of  vahular  failure  is  indicated  only 
in  the  stage  of  disturbance  in  compensation.  Here  the 
most  valuable  agent  is  digitalis,  given  in  the  form  of  Squibb's 
fluidextract  (5j).  Associated  with  this  strychnin  is  often 
used  (gr.  \  to  \  snbcutaneously).  AVhen  dropsy  sets  in  such 
drugs  as  caft'ein,  pyuretin  and  stro])!iantiius  are  indicated. 

RUPTURE    OF    THE    HEART. 

Rupture  of  the  heart,  when  not  due  to  traumatism,  is  tlie 
result  of  pathological  changes  in  the  myocardium  (fatty 
degeneration,  aneurysms,  myomalacia,  echinococcus).  The 
predisposing  causes  are  conditions  which  increase  blood- 
pressure,  such  as  excitement  (operations,  coitus,  etc.); 
tympanitis  or  severe  concussion  of  the  body  due  to  falls, 
blows,  etc.  Heart  rupture  leads  to  apoplectic  death  under 
symptoms  of  internal  hemorrliage. 

ANEURYSM    OF    THE    AORTA. 

This  is  a  rare  condition  in  animals  due  to  arteriosclerosis. 
In  horses  it  occurs  most  commonlv  at  the  root  of  the  aorta 


TUMORS  IN   THE  HEART  81 

near  the  l)ifurcation.  Aneurysm  also  occurs  in  the  anterior 
mesenteric  and  the  external  iliac  arteries  in  the  horse. 
I'sually  they  produce  no  symptoms  dmnng  life.  In  a  few 
cases  there  may  develop  symptoms  of  heart  hypertrophy 
with  disturbed  compensation  and  on  auscultation  over 
the  region  of  the  spinal  column  a  peculiar  buzzing  sound  is 
heard.  The  patient  may  also  show  epileptiform  attacks. 
Usually  death  results  suddenly  and  without  warning  from 
internal  hemorrhage. 

TUMORS    IN    THE    HEART. 

During  life  they  arc  difficult  to  diagnose.  Sometimes  they 
produce  symptoms  of  heart  weakness  or  heart  paralysis 
but  generally  are  symptomless.  The  most  common  tumors 
are  sarcomas,  fibrosarcomas,  and  the  less  common,  lipomas, 
myxomas,  fibromas,  and  osteosarcomas. 


PART  III. 
DISEASES  OF  THE  DIGESTIVE  ORGANS. 


CHAPTER  I. 
DISEASES  OF  THE  MOUTH. 

STOMATITIS. 

Forms. — Depending  on  the  cause,  anatomical  character, 
course  and  species  of  animal  various  kinds  of  stomatitis 
are  recognized.  The  same  cause  may  produce  different 
varieties  of  the  disease.  In  practice  the  following  forms 
are  distinguished:  (a)  Catarrhal  stomatitis;  (b)  vesicular 
stomatitis;  (c)  papulous  stomatitis;  (d)  mycotic  stomatitis. 

Catarrhal  Stomatitis. — Character. — A  catarrhal  inflamma- 
tion of  the  mucous  membrane  of  the  mouth. 

Occurrence. — A  very  common  disease  of  all  domestic 
animals  which  when  primary  is  due  to  irritants  of  various 
sorts  which  are  taken  into  the  mouth  voluntarily  with  the 
food  and  water  or  involuntarily  as  medicines  in  the  form 
of  drenches,  electuaries  and  boli.  Catarrhal  stomatitis  is 
secondary  to  a  number  of  infectious  diseases  (foot-and-mouth 
disease,  influenza,  Rinderpest,  etc.),  diseases  of  the  stomach 
and  bowels,  diseases  which  affect  nutrition  (anemia,  rachitis) 
and  poisoning  with  aconite,  mercury,  and  lead. 

Etiology. — The  causes  of  catarrhal  stomatitis  are  varied. 
In  considering  the  etiology  one  should  distinguish  between 
the  primary  and  secondary  forms. 

Frimarii  Form. — {a)  Direct  injuries  (sharp  bits,  rough 
forage,  foreign  bodies   [corn  cobs,  bits  of   bone  or  wood]. 


84  DISEASES  OF   THE   MO  (Til 

r<)U<j;li  iiianipulatioiis  during"  (UMital  operations,  lickt'd-olF 
l)o(ly  hairs,  etc.).  (/;)  Chemical  irritants  (])huits:  aconite, 
hellebore,  euphorhiuni,  tobacco,  digitalis;  minerals:  chloral 
h\(lrate,  bicliloride  of  mercury,  chloride  of  /inc,  various 
blisterinii  ajicnts  licked  off  the  skin),  (r)  Thermic  causes 
(hot  drenches,  frozen  food).  {d}  Fungi  (moulds,  rusts, 
smuts  and  yeasts),  (e)  Insects  (caterpillars  on  leaves  in  fall, 
leaf-lice).    (/)  Bacteria. 

Secondary  Form. — (a)  Symj)tomatic  of  diseased  teeth 
(alveolar  periostitis,  dental  caries  and  many  surgical 
conditions  of  the  teeth),  {h)  Shedding  of  dccidious  teeth 
(causing  gingivitis  or  "lampas").  (c)  Some  of  the  infectious 
diseases  (foot-and-mouth  disease.  Rinderpest,  contagious 
pustulous  stomatitis,  etc.).  ((I)  Si)read  of  pharyngitis  to 
mouth  cavity,  (c)  Most  of  the  diseases  of  the  stomach  and 
bowels.  (/)  Constitutional  diseases  seriously  affecting 
nutrition  and  resistence  (anemia,  rachitis). 

Symptoms. — In  acute  cases  the  patients  resist  attempts  to 
examine  the  mouth  ("mouth  shy"),  will  eat  slowly,  especi- 
ally roughage,  show  frequent  thirst  and  salivation.  In  the 
early  stage  (congestion)  the  mucous  membrane  of  the  lips, 
cheeks  and  tongue  is  red,  dry  and  swollen.  Later  the  tongue 
is  coated  with  a  sticky,  grayish  (greenish  in  grass-ted  horses) 
often  foamy  exudate.  The  hard  palate  is  swollen  ("  lampas") 
and  sometimes  the  tongue.  There  is  salivation  ("slobber- 
ing") a  viscid,  ropy  saliva  drooling  from  the  commissures 
of  the  lips,  especially  marked  when  the  mouth  is  opened. 
Sometimes  the  saliva  is  foamy.  It  may  be  retained  in  the 
mouth  to  be  ejected  at  inter^■als.  The  saliva  has  a  peculiar 
sweetish  odor  due  to  its  retention  and  decomposition. 

l^sually  there  are  no  marked  lesions  present.  Occasion- 
ally, however,  small,  gray  j)ai)ules  appear  on  the  teeth 
surfaces  of  the  lips  and  under  the  tongue  from  which  later 
shallow,  quick-healing  ulcers  develop.  (\)nstitutional  dis- 
turbance is  rarely  noted. 

Course. —  In  ])rimary  stomatitis  the  course  is  benign,  ending 
in  recovery  in  fourteen  days.  The  course  in  the  secondary 
form  varies  with  the  pi'iniary  disease  with  which  it  is 
associated. 


STOMATITIS  85 

Diagnosis. — The  recognition  of  stomatitis  per  s-c  is  not 
difficult.  To  determine,  however,  whether  it  is  primary  or 
secondary  is  often  not  easy,  especially  early  in  its  develop- 
ment. From  the  history,  the  temperature,  pulse  and  other 
symptoms  of  constitutional  disturbance  which  occur  in  those 
diseases  where  stomatitis  is  a  symptom,  the  diagnosis 
"secondary  stomatitis"  usually  can  be  made. 

Treatment. — Once  the  cause  is  removed  the  symptoms 
rapidly  subside.  The  principal  indications  are  to  change  the 
food,  look  after  the  teeth,  remove  any  foreign  bodies  from  the 
mouth  and  allow  the  patient  constant  access  to  good  drinking 
water.  Various  "mouth  washes"  are  recommended.  The 
following  are  examples:  Alum  water  (1  per  cent.),  creolin 
(1  to  2  per  cent.),  boric  acid  (2  per  cent.),  permanganate  of 
potash  (1  to  200).  Vinegar  one-half  pint,  common  salt  one 
tablespoonful  mixed  together  in  a  quart  of  water  is  useful. 
In  chronic  cases  nitrate  of  silver  (1  per  cent.)  is  employed. 

Vesicular  Stomatitis. — Definition. — A  sporadic,  feebly  com- 
municable inflammation  of  the  mouth  characterized  by  the 
formation  of  vesicles  in  the  mucosa. 

Occurrence. — The  disease  is  seen  in  horses  and  cattle 
only.  It  may  appear  as  an  enzootic,  affecting  a  number 
of  horses,  or  even  assume  the  proportions  of  an  epizootic, 
a  large  number  of  animals  becoming  affected  from  infested 
food. 

Etiology. — The  cause  is  not  definitely  known.  Animals 
pastured  on  fungi-infested  clovers  are  most  commonly 
attacked.  It  is  probable  that  fungi  (Uromyces  occultus, 
Polydesmus  exitiosus)  are  factors.  In  some  outbreaks  in- 
fection seems  to  ])lay  a  role.  The  disorder  is  transmissible 
by  inoculation. 

Symptoms. — Following  prodromal  sym])toms,  which  re- 
semble those  of  the  initial  stage  (congestion)  of  catarrhal 
stomatitis,  an  eruption  of  vesicles  appears  in  the  mouth 
particularly  on  the  tongue,  and  occasionally  on  the  mucous 
surface  of  the  lips,  and  at  the  commissures  of  the  mouth. 
The  vesicles  vary  in  size  from  a  grain  of  wheat  to  a 
small  bean,  are  sometimes  umbilicated  and  are  filled  with 
a  clear  serous  fluid.    In  three  or  four  days  they  eru])t,  leaving 


86  DISEASES  OF   THE   MOUTH 

])eliin(l  erosions  which  visually  Ileal  in  about  a  week.  In 
horses  healing  may  be  delayed  several  weeks.  The  patients 
are  usually  "mouth  shy,"  slobber,  and  show  impaired 
appetite.     A  mild  fever  has  been  noted  in  some  outbreaks. 

Course.     The  course  is  rai)id   and   beni<jn. 

Diagnosis. — In  horses  vesicular  stomatitis  might  be  con- 
fused with  contagious  pustular  stomatitis.  In  this  latter 
disease,  however,  pustules  appear,  the  eruption  of  which 
occurs  sinniltaneously  and  frequently  involves  the  exter- 
nal skin  of  the  nostrils  and  lips.  In  the  ox  the  disease 
is  distinguished  from  foot-and-mouth  disease  by  its  feeble 
infectiveness  (animal  inoculation),  slow  spread  and  the 
absence  of  fever  and  foot  lesions. 

Treatment. — The  same  as  in  catarrhal   stomatitis. 

Papulous  Stomatitis. — Definition. — A  benign,  contagious 
disease  of  the  mouth  of  cattle,  due  to  an  ultramicroscopic 
virus  and  characterized  by  an  eru])tion  in  the  mucosa  and 
skin  around  the  mouth  of  yellowish-gray,  flattened  ])apules. 
Pro})ably  does  not  occur  in  the  United  States. 

Etiology. — An  ultramicroscopic  virus.  The  disease  is 
readily  transmitted  to  healthy  animals  by  inoculation  into 
the  mucous  membrane  of  the  mouth,  subcutaneously  and 
intravenously.  The  mode  of  natural  transmission  is  not  yet 
known. 

Symptoms. — The  period  of  incubation  is  one  to  two  weeks. 
The  nodular  eru])ti()n  may  involve  the  muzzle,  lips  (outer 
and  inner  surface),  palate,  tongue,  cheeks,  and  gums.  The 
nodules  are  from  the  size  of  a  wheat  grain  to  a  small  ])ea, 
are  at  first  red  and  later  grayish-yellow  in  color.  Around 
each  nodule  is  an  area  of  congestion.  In  thelatter  stages 
the  centres  undergo  softening,  irregular-sha])ed  ])its  form- 
ing. The  bases  of  the  j)its  are  granular,  at  first  red  or 
black  and  later  yellow  in  color.  By  coalescence  large 
areas  (dollar-sized)  ai)j)ear.  The  condition  may  persist  for 
several  weeks.  There  is  usually'  no  general  disturbance, 
although  in  isolated  cases  fever  and  fetid  breath  have  been 
observed. 

Diagnosis. — The  peculiar,  flattened  nodules  which  a])pear 
not  (>nl\   in  tlu>  mucous  membrane,  but  also  on  the  external 


STOMATITIS  87 

skin  (muzzle)  are  significant,  ^'esicles  do  not  occur  and  the 
feet  are  not  involved. 

Prognosis. — The  disease  always  ends  in  healing. 

Treatment. — The  same  as  in  catarrhal  stomatitis.  As  the 
disease  is  contagious,  separation  of  the  affected  from  the 
healthy  is  indicated. 

Mycotic  Stomatitis. — Definition. — This  is  a  non-infective 
inflammation  t)f  the  mouth,  muzzle,  skin  of  the  region  of  the 
coronets  and  sometimes  of  the  udder  and  teats  which  occurs 
in  cattle  on  pasture.  It  is  characterized  by  the  formation 
of  minute  vesicles  and  later  ulcers  which  usually  readily  heal. 

Occurrence. — The  disease  is  quite  common  in  the  United 
vStates  among  cattle  running  at  pasture,  and  most  often 
breaks  out  in  the  fall,  esi)ecially  when  a  rainy  season  follows 
a  ])eri()d  of  drought. 

Etiology. — The  cause  of  mycotic  stomatitis  is  evidently 
certain  fungi  which  infest  grasses.  Clover  pasture  seems 
to  be  the  most  dangerous  in  this  regard.  The  disease  is 
often  enzootic,  affecting  a  number  of  animals  subjected  to 
like   condition   in   the   community. 

Symptoms. — The  initial  symptoms  are  those  of  impaired 
appetite,  painful  mastication  and  slobbering.  In  severe 
outbreaks  lameness  may  be  the  first  symptom  noticed  by  the 
owner.  On  examination  of  the  mucous  membrane  of  the 
mouth  minute  vesicles  are  noted.  Later  small  ulcers  appear, 
particularly  on  the  mucous  surfaces  of  the  lips,  under  the 
tongue  and  on  the  dental  pad.  Sometimes  gray-colored 
fibrinous  deposits  are  present.  Erosions,  scabs  and  crusts 
form  on  the  muzzle  and  external  surface  of  the  lips. 
When  the  animal  is  lame  the  skin  and  subcutis  of  the 
coronet  become  edematous,  hot  and  tender.  In  some 
instances  the  swelling  is  cracked  and  creviced  and  may 
show  evidence  of  secondary  pus  infection.  When  the  udder 
is  involved  scabs  and  fissures  appear  on  the  teats  and  skin 
of  the  udder,  causing  cows  to  resist  the  operation  of  milking. 
Milk  secretion  may  be  partially  suspended.  The  general 
condition  of  the  animal  is  involved  only  in  severe  attacks. 
They  usually  move  about  stiffly,  frequently  shaking  their 
feet,  or  when  standing  assume  the  attitude  of  a  horse  with 


88  DISEASES  OF   THE   MOUTH 

founder.  The  temperature  may  be  slitilitl\-  elevated  (mild 
fever).  There  ma>"  be  emaeiatiou  from  iiial)ility  to  eat  and 
in  rare  instances  indivi(hial  animals  may  show  diarrhea. 

Prognosis. — The  prognosis  is  good;  only  in  aggravated 
cases  are  losses  recorded  from  secondary  infection. 

Diagnosis. — The  diagnosis  is  not  difficult,  the  disease 
occurs  among  pastured  cattle,  usually  attacks  only  a  per- 
centage of  the  herd,  is  generally  benign  in  its  course,  and 
once  the  patients  are  removed  from  the  infested  pasture  the 
symptoms  rapidly  subside.  From  foot-and-mouth  disease 
it  is  distinguished  by  the  fact  that  it  is  not  transmissible 
by  inoculation,  does  not  affect  sheep  and  swine,  fails  to 
develop  the  characteristic  large  vesicles  anrl  is  less  apt  to 
involve  the  feet.  Foot-rot  and  ergotism  are  not  attended  by 
stomatitis.  Necrotic  stomatitis  of  calves  is  seen  only  in 
very  young  animals,  does  not  involve  the  external  skin  and 
the  lesions  are  characterized  by  a  necrosis  of  the  mucous 
meml)rane  of  the  mouth.    The  feet  are  not  attacked. 

Treatment. — The  principal  indication  in  treating  this 
disorder  is  to  remo\e  the  cattle  from  the  infested  pastures, 
best  placing  them  in  a  barnyard  and  feeding  soft  feeds. 
The  animals  should  be  given  constant  access  to  fresh  water. 
It  is  recommended  to  place  in  the  water  borax  (1  oz.  to  1 
gal.  of  water).  In  range  cattle  four  ounces  of  crude  carbolic 
acid  may  be  mixed  with  twelve  quarts  of  i)arrel  salt,  the 
cattle  being  i)ermitted  to  lick  this  at  will.  The  foot  lesions 
are  treated  according  to  the  general  principles  of  surgery. 
As  a  rule  the  animals  rapidly  recover  when  tliey  are  removed 
from  the  infested  pasture. 


CHAPTER  II. 
DISEASES  OF  THE  PHARYNX. 

PHARYNGITIS. 

Sore  Throat.     Angina  Simplex. 

Definition. — An  inflammation  of  tlie  pharyngeal  structures 
which  usually  involves  the  soft  palate  and  tonsils.  Pharyn- 
gitis is  frequently  associated  with  laryngitis,  and  may 
appear  as  a  primary  or  a  secondary  disease. 

Occurrence. — Horses  and  swine  are  the  principal  victims. 
Cattle  and  sheep  are  seldom  attacked.  When  due  to  infection 
pharyngitis  often  occurs  as  an  enzootic.  The  disorder  is 
most  common  in  the  spring  and  fall  wdien  weather  changes 
are  sudden  and  frequent. 

Etiology. — Primary  pharyngitis.  As  in  stomatitis,  pharyn- 
gitis may  be  due  to  direct  injury  to  the  pharynx  from  foreign 
bodies  or  chemical  substances  (strong  medicines,  poisonous 
plants,  chloroform,  etc.),  or  the  giving  of  hot  drenches. 
Refrigeration  is  a  common  predisposing  cause.  Infection 
with  streptococci  or  necrosis  bacillus  and  other  bacteria 
commonly  produce  it.  In  rare  instances  it  may  be  due  to 
parasites  (gastrus  larviie). 

Secondary  pharyngitis  may  be  due  to  a  spread  of  stomatitis, 
rhinitis  or  laryngitis  to  the  pharyngeal  mucosa  or  it  may  be 
a  symptom  of  many  of  the  specific  infectious  diseases  such 
as  strangles,  influenza,  purpura  hemorrhagica,  hemorrhagic 
septicemia,  hog  cholera,  anthrax,  etc.  In  the  horse  sup- 
purative i)haryngitis  with  peri-  or  parapharyngeal  abscess 
formation  is  usually  a  symptom  of  strangles. 

Forms. — From  a  pathological  standpoint  the  following 
forms  of  pharyngitis  are  distinguished:  (a)  The  catarrhal 
which    is   the   mildest    form,      (h)    The   suppurative   which 


00  DISEASES  OF   THE   J'lfARYXX 

usually  leads  to  abscess  formation  about  the  i)harynx.  (c) 
Croupous,  a  i)seu(lomembraue  ai)i)earing  over  the  mucous 
membrane,  (c/)  Dii)htheritic,  a  necrosis  of  the  mucous 
membrane  associated  with  which  is  j)hlegmon  and  swelling 
of  the  lymph  glands.  Diphtheritic  pharyngitis  commonly 
is  associated  with  foreign  body  pneumonia  and  general 
se])ticemia. 

Symptoms. — The  most  conspicuous  symptom  of  pharyn- 
gitis is  difficulty  in  swallowing  (dysphagia).  In  the  horse 
this  is  expressed  by  regurgitation  through  the  nostrils  of 
fluids  (drinking  water)  and  food.  In  swine  the  ])atient  holds 
the  head  and  neck  stiffly,  is  restless  and  often  squeals  when 
it  attempts  to  swallow.  In  acute  pharyngitis  the  solid  food 
may  be  ejected  from  the  mouth  after  being  partially  chewed. 
As  saliva  is  swallowed  only  in  ])art,  slobbering  is  a  common 
symptom.  The  patients  usually  hold  the  head  extended, 
nose  poked  out  and  are  disinclined  to  flex  the  head  upon 
the  neck.  Palpation  over  the  region  of  the  pharynx 
shows  the  ])arts  to  be  hot  and  tender.  There  is  usually 
bilateral  nasal  discharge  mixed  with  saliva  and  food  par- 
ticles. The  patient  usually  coughs,  especially  when  the 
upper  trachea  is  pinched  (larynx  involved).  In  severe 
cases  (phlegmon,  abscess,  diphtheritis)  there  may  be  pro- 
nounced dysi)nea  (edema  of  glottis),  rattling  sounds  in  the 
throat  and  marked  swelling  of  the  subparatoid  region.  If 
embolic  or  foreign  body  pneumonia  is  present,  the  expira- 
tion becomes  fetid,  there  is  dulness  on  percussion  over  the 
thorax  and  rales  and  bronchial  tones  on  auscultation.  Fever 
is  ])resent  in  most  cases,  esjjecially  in  those  arising  from 
infection,  the  temperature  reaching  104°  F.  Pharyngitis 
due  to  traumatism  or  chemical  action  is  only  associated 
with  fe^■er  when  secondary  infection  takes  ])lace.  If  the 
a])i)etite  is  imi)aire(l,  the  i)atient  loses  iiesh  during  the  attack. 

Diagnosis.  The  diagnosis  of  ])haryiigitis  is  usually  not 
diihcult,  esjjecially  in  animals  where  an  ocular  examination 
of  the  throat  is  possible.  In  horses,  however,  where  this  is 
not  permissible  it  is  more  difficult.  To  determine  whether 
the  condition  is  ])rimary  or  secondary  one  must  ])ay  esj)ecial 
attention   to   the   other   symi)toms   ])resent,  such   as   would 


PARALYSIS  OF   THE  PHARYNX  91 

occur  in  strangles,  influenza,  etc.  Obviously  the  examiner 
should  be  on  the  alert  for  foreign  bodies  and  tumors  in  the 
pharynx  which  produce  symptoms  of  dysphagia. 

Course. — The  course  is  very  varied.  A  simjile  catarrhal 
pharyngitis  in  horses  usually  heals  in  three  or  four  days. 
In  swine,  however,  the  termination  is  often  fatal.  Suppura- 
tive pharyngitis  leading  to  secondary  abscess  and  ulcers  are 
often  quite  obstinate  and  may  continue  until  surgical  inter- 
ference provides  drainage  for  the  pus.  Pharyngeal  paralysis 
and  roaring  are  not  uncommon  sequehie.  Death  may  occur 
from  asphyxia,  septic  infection  or  intoxication  or  from 
pulmonary  gangrene. 

Treatment. — The  patient  should,  if  possible,  be  placed  in 
a  warm,  well- ventilated  stable  free  from  dust  and  irritant 
gases.  Only  soft  foods  (gruels,  bran  mashes,  grass)  should 
be  fed.  In  swine,  milk  may  be  given.  In  horses  where 
dysphagia  is  complete  on  account  of  the  danger  of  even  fluids 
entering  the  lungs  the  patient  should  be  made  to  fast  for 
two  or  three  days  or  fed  and  watered  through  a  stomach- 
tube  or  through  the  rectum.  Chlorate  of  potash  (1  oz.  to 
2  gals,  of  water)  is  popularly  used.  For  threatening  dyspnea 
tracheotomy  should  be  employed.  Subparotid  abscesses 
should  be  opened  and  drained.  Local  applications,  hot 
water  (Priessnitz  cataplasm)  are  helpful.  Infrictions  of 
gray  mercurial  ointment  are  recommendable.  Strong 
blistering  liniments,  however,  should  be  avoided.  Local 
applications  are  too  dangerous  in  the  larger  animals.  Drench- 
ing should  be  prohibited.  When  the  patient  is  able  to  swallow, 
expectorants  such  as  tartar  emetic  and  ammonium  chlorid 
combined  with  powdered  licorice  root  may  be  given  as  an 
electuary.  Symptoms  of  septicemia  (high  temperature, 
rapid  pulse,  muddy  mucous  membranes,  etc.),  are  best 
combated  with  large  doses  of  oil  of  camphor  administered 
subcutaneously.  In  swine  when  suffocation  threatens,  an 
emetic  should  be  given  (white  hellebore  or  ipecac,  grains  xxv). 

PARALYSIS  OF  THE  PHARYNX. 

Definition. — Any  condition  of  the  ])har>'nx  which  interferes 
with  swallowing. 


92  DISEASES  or  THE  PHARYNX 

Etiology. — Paralysis  of  the  i)liarynx  is  usually  secondary 
to:  (a)  An  acute  j)haryngitis  which  accompanies  an  attack 
of  strangles  (parai)haryngeal  abscess).  (6)  Forage  poisoning 
of  which  it  is  often  a  prominent  symptom,  (r)  Bulbar 
])aralysis  in  diseases  of  the  central  nervous  system  (menin- 
gitis, cerebrosi)inal  meningitis),  (r/)  Tumors  in  the  i)harynx 
(cysts,  papillomas,  polypi,  carcinomas)  and  more  rarely 
along  the  course  of  the  pneumogastric  nerve,  {e)  In  certain 
infectious  diseases  (rabies,  acute  infectious  bulbar  paralysis 
of  cats).  (/)  In  certain  intoxication  diseases  (parturient 
paresis  of  cows.) 

Symptoms. — The  principal  symptom  is  dysphagia.  In 
horses  and  cattle  food  and  water  mixed  with  saliva  are 
regurgitated  through  the  nose.  If  no  food  is  taken  drooling 
from  the  mouth  occurs.  Attenii)ts  at  swallowing  produce 
loud,  gurgling  sounds.  Palpation  of  the  pharynx  through 
the  mouth  fails  to  i)r()duce  contraction  of  the  pharyngeal 
muscles. 

Course.  The  course  depends  upon  the  cause.  When  due 
to  inflammation  healing  may  follow  in  a  few  weeks  (rui)ture 
of  abscess).  The  successful  removal  of  tumors  will  im- 
mediately arrest  the  symptoms.  When  due  to  forage 
l)oisoning  or  acute  diseases  of  the  central  nervous  system 
(rabies,  bulbar  i)aralysis)  the  course  is  rapid  and  fatal. 
In  i)arturient  paresis  most  cases  recover  under  modern 
treatment  (air  inflation  of  the  udder).  As  a  general  propo- 
sition prolonged  paralysis  of  the  pharynx  is  serious,  as  it 
l)revents  the  i)r()i)er  nutrition  of  the  ])atieiit,  and  from  food 
and  saliva  entering  the  wind])ii)e  and  lungs  frequently  is 
followed  by  fatal  foreign  body  i)neum()nia. 

Diagnosis. — A  careful  ])ali)ati()n  and  ins])ection,  when 
possible,  of  the  i)harynx  should  be  made  in  all  cases  to 
exclude  foreign  bodies  (corn  cobs,  pieces  of  wood,  etc.)  or 
to  determine  whether  tumors  or  parapharyngeal  abscesses 
are  j)resent. 

Treatment. — As  noted,  in  cases  of  paralysis  due  to  acute 
infiauMiiation  (abscess)  a  s])ontane(>us  recovery  may  occur. 
Surgical  intervention  is  often  effective  (see  Surgery).  Blisters 
and  the  electric  battery  ai)plie(l  to  the  external  throat  rarely 


PARASITES  IX   THE   PHARYXX  93 

do  much  good.  Subcutaneous  injections  of  nerve  tonics 
(strychnin  nitrate  gr.  j-^  once  daily)  are  recommended. 
While  the  patient  is  unable  to  swallow  it  should  be  fed  through 
a  stomach-tube.  Obviously  animals  suffering  from  rabies 
should  be  destroyed. 

PARASITES  IN  THE  PHARYNX. 

Larvae  of  the  bot  hies  (Gastro])hilus  equi  and  G.  ha?mor- 
rhoidalis)  sometimes  are  found  attached  to  the  upper  wall 
of  the  pharynx.  In  rare  instances  they  have  been  known 
to  induce  severe  pharyngitis,  or  by  entering  the  larynx, 
suffocation. 

Horse  leeches  (Hsemopis  sangui  suga)  affect  horses  and 
mules  in  southern  countries.  They  attach  themselves  to 
the  wall  of  the  pharynx  and  suck  blood.  Their  presence  is 
suspected  from  nasal  and  buccal  hemorrhage  which  they 
occasionally  induce.  Large  numbers  may  cause  fatal  loss 
of  blood  or  serious  anemia.  The  treatment  usually  advised 
is  to  irrigate  the  throat  with  salt  and  vinegar  or  creolin 
(2  per  cent.).  Lihalation  of  turpentine  or  ammonia  fumes 
is  also  useful.  Prevention  consists  in  filtering  the  drinking 
water. 

Hungarian  flies  (Simulia  columbacoeusis)  attack  Hungarian 
cattle  and  sometimes  reach  the  pharynx  through  the  mouth 
and  nose.  Occasionally  they  produce  serious  pharyngo- 
laryngitis,  leading  to  suffocation. 


CHAPTER   III. 
DISEASES  OF  THE  STOMACH  AND  BOWELS. 

GASTRO-INTESTINAL  CATARRH  OF  THE  HORSE. 

Catauriial  Gastko-enteritis. 

Definition. — A  catarrhal  inflammation  of  the  mucous 
memhranc  of  the  stomach  and  bowels.  While  it  occurs  as  a 
l)rimary  disease,  it  is  often  a  secondary  condition.  It  may 
be  acute  or  chronic. 

Occurrence. — Gastro-intestinal  catarrh  is  a  \'ery  common 
disease  of  horses. 

Etiology. — Primary  gastro-intestinal  catarrh  is  due  to: 
(a)  Bad  food  (mouldy  forage,  smutty  oats,  rotten  straw), 
forage  containing  irritant  weeds  or  sharp  objects.  Food 
which  is  too  hot  or,  on  the  other  hand,  frozen  and  food  con- 
taining foreign  material,  as  sand. 

(b)  (iood  food  injudiciously  fed.  (Too  rai)id  eating  with 
incomj)lete  mastication  when  very  hungrx ,  not  enough 
saliva  being  mixed  with  food  hastily  swallowed;  oxerloading 
stomach.  Sudden  change  from  accustomed  to  unaccustomed 
foods,  as  oats  to  corn,  corn  to  barley  or  wheat,  etc.) 

{(')  Water.  Large  (luantities  of  cold  water  when  hot  and 
fatigued.     Water  from  stagnant  pools. 

(f/)  Disturbance  in  mastication  (bad  teeth). 

(e)  Psychic  influences.  (Extreme  nervousness  in  race 
horses,  casting,  tying  head  too  high,  pain  following  operations 
or  wounds.) 

(/)  Animal  parasites   (ascarides). 

(g)  Irritant  drugs  and  poisons  (arsenic,  calomel,  acids, 
alkalies). 

Chronic  gastro-intestinal  catarrh  is  due  to  much  the  same 
causes  as  the  acute  but  acting  less  intensively.    They  are: 

(a)  Bad  food  (sanded  food,  frozen  food). 

(6)   Improjier  feeding. 


CASTRO-INTESTINAL  CATARRH  OF   THE  HORSE     95 

(c)  Bad  teeth  (sharp  teeth,  split  teeth,  alveolar  periostitis, 
caries,  etc.)- 

(d)  Vices  (wind  sucking,  cribbing). 

(e)  Chronic  diseases  of  liver,  lungs,  heart  (induce  congestion 
of  portal  system). 

(/)  Parasitism. 

(g)  Senility  (most  decrepid  "  anatomy  skates"  suffer  from 
chronic  gastro-intestinal  catarrh). 

Acute  gastro-intestinal  catarrh  is  secondary  to  acute 
general  infectious  diseases  (influenza,  strangles),  blood 
diseases  (anemia,  leukemia,  pseudoleukemia,  etc.).  It  may 
also  be  embolic  in  origin  from  strongylus  armatus  in  anterior 
mesenteric  artery. 

Symptoms. —  Gastric  Symjitoms. — 'Impaired,  lost  or  capri- 
cious appetite.  In  some  cases  the  appetite  is  vitiated  (eat 
unnatural  th  ings) .  The  patients  drink  little  water.  Tendency 
to  yawn  and  vomiting  is  rare.  The  mucous  membranes  are 
"muddy,"  discolored,  those  of  the  mouth  often  coated  with 
soapsuds-like  foam.  The  expirium  is  sweetish,  nauseating. 
The  pulse,  respirations  and  temperature  are  usually  little 
affected  in  primary  cases.  The  patient  is  languid,  lazy, 
sweats  and  tires  easily  when  at  work. 

Intestinal  Symptoms. — If  the  stomach  is  not  involved 
appetite  may  be  normal.  If  diarrhea  exist  there  is  great 
thirst.  The  peristalsis  is  lively  and  the  borborygmus  may 
be  audible  quite  a  distance  from  the  patient.  Colicky  pains, 
especially  after  eating  or  drinking.  Dung  passed  at  first 
in  small,  hard,  mucus-covered  pellets,  later  softer  (cow-dung 
consistency)  and  finally  diarrhea,  the  discharges  very  fluid 
and  fetid.  Anal  flatus  is  frequent,  loud  and  fetid.  Some 
patients  are  sensitive  to  palpation  over  region  of  small 
bowels.  Icterus  appears  if  duodenum  is  involved.  Urine 
is  acid;  indican  increased.  In  chronic  cases  on  account 
of  the  irreparable  connective-tissue  thickening  of  the  bowel 
mucous  membrane  and  the  atrophy  of  the  glands  the  nutri- 
tion of  the  organism  suffers.  The  patient  loses  flesh,  the 
abdomen  becomes  "tucked  up,"  the  hair  coat  dull,  long 
and  erect,  the  skin  "scurfy,"  harsh,  inelastic  and  leather- 
like ("hide  bound").     Anemia,  emaciation,  cachexia  appear 


OC)         DISEASES   OF    THE   STOMACH    AM)    HOW  ELS 

toward  tlu'  end.  \('rti^()  and  syiiij)t(>ms  of  iinmobility 
a])|)('ar  in  sonic  cases. 

Course  and  Prognosis.—  Acute  <i:astr(>-intcstinal  catarrh 
usually  heals  in  three  to  seven  days  if  the  case  is  properly 
handled.  It  rarely  becomes  chronic.  Chronic  cases,  how- 
ever, with  frequent  exacerbations  and  remissions,  last  for 
months  and  finally  lead  to  death  from  inanition.  The 
prt)fi;nosis  in  acute  cases  in  very  younj;  or  very  old  j)atients 
is  less  favorable.  The  mortality  is  about  1  per  cent.  Chronic 
catarrhs  are  nnich  more  serious  and  especially  in  old  horses 
with  bad  teeth  and  where  a  prolonged  treatment  with 
reuulation  of  the  diet  is  not  feasible,  usually  end  in  death. 

Treatment. — A  hygienic  and  dietetic  treatment  is  all 
important.  The  surroundings  of  the  patient  should  be  light, 
clean  and  w(>ll  \entilated.  (irood  grooming  should  be  insisted 
upon.  Examine  and  if  necessary  "dress"  the  teeth.  In 
acute  catarrh  it  is  advisable  to  withhold  food  for  two  or 
three  days  or  permit  only  small  quantities  of  easily  digested 
food  (fresh  grass,  fine  timothy  hay.  linseed  meal,  bran 
mashes  if  palatable  to  ])atient).  The  following  mixture  is 
suggested:  oats  2  parts;  bran  1  part;  malted  barley  1 
part.  Scald  or  steam  and  let  stand  twenty-four  hours,  then 
feed.  A  teacui)ful  of  linseed  which  has  been  boiled  to  a 
jelly  in  a  gallon  of  water  and  jxiured  over  a  bran  mash  is 
useful.  Allow  the  patient  plenty  of  salt  and  free  access  to 
water.  The  medicinal  treatment  is  largely  symptomatic. 
In  overloading  of  the  stomach  use: 

1 

I^ — -Hydnirnyri  chlDiid Jiv 

Piilv.  saccliaii 5U 

M.  f.  i)»ilv.  Nr.  iv. 
Sig. — OiK'  daily. 


I^ — Arccaliii jir.  ss 

.'V(iu.  dest Siiss 

M.  D.  S. — One  doso  siihcutaiu'ovisly. 

:3 

To  aiTost  fcrnioiitat.ion: 

I^-.\iid  liydrochlor 5ss 

In  buclvct  of  diinkiuf;  water. 


BLOATING  IN   THE  OX  97 

Or: 

4 

H — Crcoliiii  Pearsonii 5ss 

Pulv.  rad.  glycyrrhiza 5J 

Pulv.  althie  et  aqu.  q.  s.  f.  boli  Nr.  iij. 
.Sif;. — Daily  one  bolus. 

5 

I^ — Sodii  sulph S^ss 

Potassii  sulph tir.  xv 

Sodii  bicarb Sivss 

Sodii  chlorid 3iiss 

Sig. — Tablcspoonful  in  each  feed. 

To  the  above  gentian,  rhubarb  or  calamus  may  be  added. 
Diarrhea  is  combated  by  employing  first  a  laxative  followed 
with  antiseptics  (creolin  (§j)  or  opium  (5j)  or  styptics  such 
as  tannin  (oj),  acetate  of  lead  (3j),  silver  nitrate  (gr.  x-xv) 
dissolved  in  rain  water).  Starch  water,  alum  water  per  rec- 
tum or  a  solution  of  silver  nitrate  (1  to  500),  alum  or  tannin 
(2  per  cent,  solution)  are  very  useful  in  persistent  diarrheas. 

In  threatened  collapse  oil  of  camphor  (5ij)  subcutaneously. 

BLOATING  IN  THE  OX. 

Tympanites. 

Definition. — A  rapid  distention  of  the  abdomen  of  cattle 
due  to  gas  formed  from  the  fermenting  contents  of  the 
rumen  and  reticulum. 

Occurrence. — A  very  common  disorder  especially  among 
cattle  on  pasture  during  hot,  damp  weather.  Clover  and 
alfalfa  pastures  are  most  dangerous  in  this  regard. 

Two  clinical  forms  of  bloating  are  recognized. 

1.  Acute  tympany.  2.  Chronic  or  periodical,  mild 
tympany. 

Etiology. — 1.  Acute  tympany,  (a)  Pasturing  or  feeding 
green  grasses,  especially  legumes  such  as  clover,  red  clover, 
alfalfa,  vetches,  peas,  or  such  foods  as  buckwheat,  swamp- 
grasses,  etc.  Such  grasses  are  most  dangerous  just  before 
they  bloom,  particularly  when  wet  with  rain  or  dew.  Young 
grass  growing  in  stubble  fields  is  a  common  cause.  (6) 
Feeding  foods  which  readily  ferment,  such  as  potatoes,  beets 
7 


1)8         DISEASES  OF   THE  STOMACH   AM)  BOWELS 

(residue  of  sugar  beets),  malt,  withered,  heated  grass,  etc. 
(c)  Certain  toxic  plants  (spotted  hemlock,  water  liemlock, 
colchicum,  tobacco),  (rl)  Occlusion  of  the  esophagus  (choke) 
will  induce  bloating  if  the  stomach  contents  are  of  a  kind 
which  easily  ferments. 

Symptoms.— There  is  a  rai)id  distention  of  the  abdomen, 
especially  of  the  left  side.  The  abdomen  assumes  the  shape 
of  an  a])ple  and  is  of  the  consistency  of  a  i)artially  inflated 
I)neumatic  tire.  On  ])ercussi()n  a  hyperresonant  tone  is 
emitted.  On  auscultation  no  ])eristalsis  is  audilile.  The 
l)atient  is  usually  quite  dysj)neic  (mechanical  com])ression 
of  lungs,  CO2  intoxication)  breathing  with  open  mouth 
and  tongue  protruding.  The  mucous  membranes  become 
cyanotic,  there  is  restlessness,  loss  of  appetite,  sup])ressed 
rumination  and  eructation  of  gas  through  the  esophagus. 
Regiu'gitation  of  food  masses  occurs  occasionally. 

Diagnosis. — Usually  easy.  The  rapid  distention  of  the 
abdomen,  characteristic  indications  of  gas  on  percussion, 
dysi)nea  and  anxiety  suffice  for  a  diagnosis.  Chronic  bloat 
is  much  slower  in  develoj^ment  and  does  not  lead  to  serious 
distention.  The  bloating  which  attends  choke  has  a  different 
history,  belching  is  absent  and  by  using  the  probang  the 
obstruction  is  encountered. 

Course. — The  course  is  rai)id,  in  some  cases  the  accumulation 
of  gas,  which  occupies  only  an  hour  or  so,  leads  to  death  from 
asphyxia  (CO?  intoxication)  in  a  few  hours.  Other  cases 
develop  slower,  the  excess  gas  being  belched  out  from  time 
to  time,  e\entually  leading  to  s])()ntane()us  recovery. 

Prognosis. — Acute  bloating  is  always  serious,  especially 
in  sheep.  If,  however,  treatment  is  promjjt  and  properly 
administered  recovery  soon  follows. 

Treatment. — Various  methods  of  relie\ing  bloating  are 
reconunended.  Generally  s])eaking  they  may  be  ])Iace(l  in 
one  of  two  groups:  («)    Palliative;  {h)   Radical. 

(a)  Among  palliative  measures  are:  (a)  Kneading  the 
abdomen.  The  abdomen  is  gently  but  firmly  massaged  by 
the  knee  of  the  o])erator,  the  fore  ])arts  being  elevated  by 
standing  the  ])atient  on  a  steep  incline.  Sheep  may  be  made 
to  stand  on  their  hind  legs.     I)ri\ing  the  ])atient  up  a  steep 


BLOATING  IN  THE  OX  99 

liill  yields  good  results  in  milder  cases,  (h)  Cold  water 
irrigation  to  the  flanks.  Bloated  sheep  may  be  driven 
through  a  stream  of  water,  (c)  Inducing  belching  by  irri- 
tating the  throat  with  a  blunt  instrument  inserted  through 
the  mouth,  the  tongue  being  drawn  forward.  Less  efficient 
is  the  use  of  a  bit  made  of  twisted  straw  and  smeared  with 
tar.  (d)  Passing  a  hollow  probang  is  rarely  of  value,  as  it 
soon  becomes  blocked  with  food  masses.  In  severe  dyspnea 
it  is  contra-indicated.  That  the  above  cited  methods  may 
be  combined  is  obvious,  (e)  So-called  "absorbent"  drugs 
are  sometimes  employed  (burnt  magnesia,  10  per  cent.; 
lime  water,  spirits  of  ammonia,  2  per  cent.,  and  soap  2  per 
cent.).  Turpentine  in  oil  (§ij  to  Oj  of  oil)  or  formalin  (5ss 
to  water  Oij),  are  commonly  employed.  Veratrin,  creolin 
and  alcohol  are  sometimes  given.  The  use  of  drugs  in  the 
treatment  of  acute  bloating  plays  a  very  subordinate  part. 
The  effect  is  largely  due  to  the  belching  which  the  act  of 
drenching  induces. 

(h)  Radical  measures:  When  the  life  of  the  patient  is 
threatened  by  severe  dyspnea  or  the  application  of  the 
palliative  measures  are  not  advisable  or  have  proven  in- 
sufficient, puncturing  the  rumen  with  a  trocar  is  often  life 
saving.  The  instrument  which  should  be  sterile  is  plunged 
into  the  centre  of  the  triangle  forming  the  hollow  of  the  left 
flank,  or,  in  case  the  landmarks  are  obliterated  by  the 
bloating,  where  the  distention  is  greatest.  If  time  is  available, 
shaving  and  disinfecting  the  skin  at  the  point  of  operation  is 
recommended.  In  withdrawing  the  canula  the  trocar  should 
be  first  inserted  and  care  taken  that  the  skin  is  not  pulled 
loose  from  the  underlying  connective  tissue,  as  this  permits 
air  to  enter  and  may  lead  to  infection.  In  case  the  operation 
must  be  repeated  it  is  advisable  to  make  a  fresh  wound  rather 
than  use  the  old  puncture.  In  thick-skinned  animals  an 
incision  through  the  skin  only  may  be  made  with  a  sharp 
bistoury  which  facilitates  the  insertion  of  the  trocar.  After 
withdrawing  the  trocar  the  wound  may  be  dressed  with 
tar  or  any  antiseptic.  After  the  bloating  is  relieved  the 
patient  may  be  given  a  physic  (Glauber's  salts,  1  lb.,  oil  Oj), 
and  give  a  restricted  diet. 


10(1       DISEASES  OF   THE  STOMACH   AND  HOW  ELS 

Prophylaxis. — It  is  rccommendable  to  feed  cattle  about  to 
be  placed  on  clover  or  alfalfa  pastures  a  quantity'  of  dry  ha>- 
before  beinp;  turned  out.  Cattle  tjniziuj;  in  fields  covered 
with  rich  ])asture  or  sheep  on  stubble  fields  should  l)e  care- 
fully watched  by  atteudants.  Farmers  should  keep  trocars 
handy,  as  in  acute  prinuiry  bloat  a  veterinarian  cannot 
always  be  called  early  enough  to  prevent  death. 


CHRONIC  OR  HABITUAL  TYMPANY. 

Etiology. — This  form  of  bloatinji;  which  is  milder  than  the 
acute  ])riniary  is  always  a  secondary  condition.  It  is  usually 
due  to:  {a)  chrouic  gastro-intestinal  catarrh,  {b)  Adhesions 
sometimes  the  result  of  traumatic  indigestion,  (r)  Tuber- 
culosis of  the  mediastinal  lymph  glands  which  press  upon 
the  esophagus  so  reducing  its  lumen  that  belching  is  inter- 
ferred  with,  {d)  Hair  balls  iu  cattle  and  wool  balls  in  sheep 
(infrequent),  [c)  Stenosis  or  impaction  of  the  intestines 
(rare). 

Symptoms. — The  symptoms  consist  in  a  gradually  develop- 
ing usually  moderate  distention  of  the  left  flank.  The 
coudition  is  usually  an  intermittent  one  and  an  attack 
follows  the  ingestion  of  food  which  easily  ferments.  In  a  few 
individuals  the  distention  may  be  permanent.  There  is 
usually  not  much  disturbance  of  the  general  condition.  The 
animal  may  eat,  ruminate  and  seem  in  normal  health  except 
for  the  distention  of  the  abdomen.  In  some  cases  the  i)atient 
may  show  symptoms  of  indigestion. 

Diagnosis. — The  diagnosis  of  chronic  tympany  is  usually  not 
difhcult,  although  to  determine  the  exact  cause  of  it  during 
the  life  of  the  i)atient  may  be  impossil)le.  It  is  ad\isable  in 
all  cases  to  test  the  animal  with  tuberculin,  and  at  the  same 
time  carefully  sound  the  esophagus  with  a  ])robang  to  see 
whether  tuberculosis  exists  or  not. 

Prognosis.  \Vhile  chronic  tymi)any  usually  does  not  lead 
to  immediate  death  the  prognosis  is  more  serious  than  in 
acute  primary  bloating,  as  the  causes  cannot  always  be 
removed. 


SO-CALLED  COLICS  OF   THE  HORSE  101 

Treatment. — The  treatment  is  practically  the  same  as 
that  suggested  for  acute  tympany  to  relieve  bloating.  This 
may  be  followed  by  the  treatment  advised  for  indigestion 
in  cattle.  Where  there  is  reason  to  believe  that  the  inter- 
mittent bloating  is  due  to  some  foreign  body  in  the  stomach, 
rumenotomy  may  be  performed  for  relief.  This  is  especially 
indicated  in  periodic  tympany  of  calves. 

SO-CALLED  COUCS  OF  THE  HORSE. 

The  term  colic  is  a  collective  one  and  applies  to  all  con- 
ditions which  cause  abdominal  pain.  Colic  is  therefore  a 
symptom  and  not  a  disease.  \Yhile  most  abdominal  pains 
come  from  the  stomach  and  bowel  they  may  also  eminate 
from  a  number  of  other  organs.  Acute  diseases  of  the  peri- 
toneum, liver,  kidneys,  lu-inary  bladder,  uterus,  ovaries, 
esophagus  and  pleura  (rarely)  may,  too,  be  accompanied  by 
symptoms  usually  termed  "colic."  To  consider  all  con- 
ditions in  the  horse  which  produce  more  or  less  violent 
abdominal  pain  a  specific  disease,  and  to  treat  them  all  more 
or  less  alike,  is  unscientific  and  a  menace  to  the  patient. 

In  the  older  literature  abdominal  pain  due  to  stomach  and 
bowel  disorders  were  called  "true  colics,"  while  abdominal 
pains  originating  in  other  organs  were  known  as  "false 
colics." 

Were  it  possible  in  all  cases  to  make  an  accurate  diagnosis 
the  clinical  term  "colic"  would  disappear  from  veterinary 
as  it  has  from  human  medicine. 

The  principal  conditions  which  produce  severe  gastro- 
intestinal pain  named  in  order  of  frequency  are:  (a)  Impac- 
tions of  masses  of  feces  in  the  small  and  large  intestines. 
(6)  Impactions  of  the  small  or  large  intestines  complicated 
with  displacement  of  the  bowel,  (c)  Distention  of  the 
stomach  with  food  masses  or  gas,  and  (d)  A  primary  inflam- 
mation of  the  walls  of  the  stomach  and  bowels. 

Simple  impactions,  impactions  with  displacement  and 
distention  of  the  stomach  may  become  complicated  by 
rupture  of  the  wall  leading  to  peritonitis  or  peritoneal 
sepsis.     Following   displacements   enteritis   and   peritonitis 


102      DISEASES  OF  THE  STOMACH  AND  BOWELS 

usually  occur  and  from  the  absorption  of  toxins  and  bacteria 
contained  in  the  stationary  fecal  mass  an  intoxication  or 
infection  of  the  ])atient  may  result.  As  a  general  proj)osition 
gastro-abdominal  pain  appears  suddenly,  lasts  for  several 
hours  and  ends  in  the  recovery  or  death  of  the  patient. 
Occasionally,  however,  due  to  some  organic  lesion  in  the 
bowel  wall  (stenosis,  tumors,  ulcers  or  abscesses,  diverticula, 
dilatation  of  the  cecum)  or  hernias  or  intestinal  stones  or 
parasites,  the  symptoms  of  pain  may  last  for  several  days 
or  weeks.  They  are,  however,  usually  intermittent  and 
not  continuous. 

Etiology. — In  general  those  symptoms  of  pain  in  the  horse 
which  were  formerly  designated  "true  colics"  are  due  to 
causes  which  may  be  classified  under  two  groups:  (1) 
Predisposing,  which  may  be  either  anatomical  or  patho- 
logical, and  (2)  exciting  or  immediate  causes. 

1.  Predisposing  Causes. — Anaiomical. — To  the  ana-, 
tomical  causes  may  be  ascribed  the  peculiar  anatomical 
arrangement  of  the  stomach  and  bowel  in  the  horse.  The 
small  stomach  and  peculiar  im])lantation  of  the  gullet  which 
make  vomiting  difficult,  long  mesentery,  narrow  ileocecal 
opening,  the  pouch-like  dilatation  and  funnel-like  termina- 
tion of  the  right  upper  colon,  the  pelvic  flexure,  and  the 
large  cecum  with  both  of  its  openings  at  the  upi)er  end, 
are  the  principal  anatomical  factors  which  interfere  with 
the  normal  i)rogress  of  the  ingesta. 

Pathological.— Diseases  of  the  digestive  organs:  for 
instance,  diseases  and  irregularities  of  the  teeth,  catarrh  of 
the  mucosa  of  the  stomach  and  bowels,  internal  abscesses, 
paralysis  with  dilatation  of  the  cecum  or  rectum,  stenosis 
of  the  ileum,  tumors,  hernias,  enteroliths  and  animal  parasites 
in  the  bowel  and  bloodvessels. 

2.  Exciting  Causes. — The  exciting  causes  of  gastro- 
abdominal  pains  are  found  chiefly  in  the  food.  Good  food 
if  taken  in  too  large  quantities,  food  which  is  unfit  (wet 
straw),  sudden  changes  from  one  kind  of  food  to  another, 
food  difficult  to  digest  (rye,  barley),  food  which  is  ferment- 
ing (new  hay,  new  oats,  new  corn)  food  infested  with  fungi, 
or  toxic  plants,  and    feeding  at  irregular  intervals  are  the 


SO-CALLED  COLICS  OF   THE  HORSE  103 

principal  exciting  causes.  Indirectly  the  weather  is  of  im- 
portance. Very  hot  or  cold,  damp  weather  which  no  doubt 
influences  metabolism  is  an  etiological  factor  to  be  reckoned 
with.  Finally,  overexertion,  especially  in  hot  weather  and 
after  a  heavy  feed,  or,  on  the  other  hand,  lack  of  exercise 
are  causes.  In  rare  instances  the  vice  known  as  "wind 
sucking"  may  induce  gastric  distention  and  pain. 

Statistics. — Morbidity. — About  10  per  cent,  of  all  the 
diseases  of  horses  and  about  50  per  cent,  of  all  of  the  inter- 
nal diseases  are  attended  by  gastro-intestinal  pain.  The 
mortality  is  about  10  per  cent.,  divided  as  follows: 

Displacement  of  colon  ■ 1.5  per  cent. 

Volvulus  of  small  intestine 1.5  " 

Rupture  of  stomach 1.5  " 

Simple  obstipation 1.5  " 

Rupture  of  cecum 1.0  " 

Rupture  of  colon 1.0  " 

Embolism,    tumors,    enteroliths,    hernias,    and 

animal  parasites 1.0  " 

Forms. — From  a  practical  standpoint  so-called  colics  may 
be  classified  as. follows: 

(a)  Acute   dilatation   of   the    stomach. 

(b)  Simple  impaction  of  the  intestines  (small  or  large 
intestines). 

(c)  Impaction  complicated  with  displacement  of  bowel. 

(d)  Embolic  colic. 

(e)  Spasmodic  colic. 
(/)  Worm  colic. 

Acute  Dilatation  of  the  Stomach  (Gasirectasis). — Defini- 
tion.— By  acute  dilatation  of  the  stomach  we  understand  a 
sudden  gaseous  distention  of  the  organ  due  to  an  unusual 
fermentation  of  its  contents.  A  primary  and  a  secondary 
dilatation  are  distinguished. 

Occurrence. — This  condition  is  not  uncommon  in  horses, 
forming  about  10  per  cent,  of  the  cases  of  colic. 

Primary  dilatation  is  due  to  overfeeding  or  more  commonly 
to  irrational  feeding,  especially  where  large  quantities  of  corn, 
barley,  bran  or  chop  are  fed.  Horses  which  are  fed  irregularly, 
such  as  cab  horses,  express-wagon  horses,  etc.,  which  often 


104       DISEASES  OF   THE  STOMACH   AXD  BOWELS 

eat  their  feed  out  of  a  nose  bag  and  are  placed  at  hard  work 
too  soon  thereafter  are  the  most  frequent  sufferers.  On  the 
other  hand,  liorses  which  are  regularly  fed  or  on  pasture  are 
only  occasionally  attacked.  There  can  be  no  doubt  that 
extremes  in  atmospheric  temi)eratiwe  may  ])redis])()se  an 
animal  to  an  attack.  It  is  commonly  observed,  therefore, 
during  very  hot  weather,  especially  when  humid,  or  on  the 
other  hand,  during  very  cold  weather,  j)articularly  when  damp. 

Secondary  dilatation  is  due  to  stasis  of  the  gastric  contents 
resulting  from  impaction  of  the  bowel  (either  simple  or 
complicated).  Secondary  dilatation  is  more  common  than 
primary. 

Diagnosis. — As  a  general  ])roposition  gastric  dilatation 
may  be  diagnosed  if  a  clear  history  of  the  kind  of  work, 
food  and  method  of  feeding  is  obtainable,  and  a  careful 
examination  of  the  patient  made.  In  most  cases  the  attack 
of  gastric  pain  comes  on  just  after  feeding  or  in  some  cases 
during  feeding.  However,  there  are  exceptions  to  this  and 
attacks  are  not  infrequent  as  long  as  seven  or  eight  hours 
after  the  consumption  of  a  meal.  The  patient  is  usually 
dyspneic  which,  de])ending  upon  the  degree  of  the  dilatation, 
will  vary.  It  is  usually  ({uite  marked,  however,  and  due  to  the 
hindrance  offered  the  diaphragm  by  the  distended  stomach. 
The  dyspnea  increases  when  the  animal  lies  down.  The 
exi)ression  of  the  face  is  usually  staring  and  anxious.  The 
conjunctiva  in  the  early  stages  is  slightly  congested,  in 
severe  cases  cyanotic  and  "muddy."  Depending  ui)on  the 
duration  and  the  severity  of  the  attack  the  pulse  varies  from 
normal  frequency  and  strength  to  weak,  often  imperceptible, 
the  number  going  as  high  as  SO  to  100.  The  tem])crature 
varies  between  100.4  to  101.9°  F.,  although  where  the  con- 
dition is  protracted  it  often  reaches  104.5°  F.  Symi)toms 
of  pain  are  usually  not  very  marked  except  in  the  beginning. 
The  intestinal  peristalsis  in  nearly  every  case  is  ])artially 
or  entirely  supj)ressed  due  to  the  associated  invohemcnt  of 
the  bowel.  In  mild  attacks  there  is  usually  little  or  no 
sweating,  but  in  severe  cases  the  sweat  outbreak  may  be 
])r()fuse.  A  symptom  of  great  diagnostic  importance  but 
luifortunatcly   not  alwa\s  jjrcsciit   is  esophageal  eructation 


SO-CALLED  COLICS  OF   THE  HORSE  105 

(in  4S  out  of  142  cases,  Behrens).  Vomiting  is  an  occasional 
symptom  which  by  no  means  speaks  for  rupture  of  the 
stomach.  In  not  over  20  per  cent,  of  the  cases  of  vomiting 
does  rupture  precede  or  follow  the  act.  Rupture  of  the 
stomach  not  infreciuently  is  the  result  of  dilatation  and  is 
often  not  attended  by  vomiting.  A  very  valuable  aid  to 
diagnosis  is  the  use  of  the  stomach-tube,  through  which, 
when  introduced,  is  discharged  a  large  quantity  (2  to  5  gal.) 
of  fluid,  gaseous,  acid,  partially  digested  food.  Unless  the 
gastric  dilatation  is  complicated  with  intestinal  disorder  a 
rapid  disappearance  of  the  symptoms  of  colic  follow  the  use 
of  the  tube.  According  to  some  authorities,  displacement  of 
the  spleen  is  a  tangible  symptom  of  gastric  dilatation. 
This  organ  may  be  felt  through  the  rectum,  where  it  has 
become  displaced  posteriorly  lying  in  the  region  of  the 
left  flank.  In  as  much  as  such  a  displacement  has  been 
ncted  in  apparently  healthy  and  even  fasting  horses  this 
symptom  is  not  pathognomonic.  While  the  spleen  may  be 
reached  per  rectum,  it  is  sometimes  difficult  to  feel  it  through 
the  wall  of  the  bowel  overlying  the  hand. 

Course. — In  mild  cases  the  symptoms  may  subside  in  a 
few  hours,  but  very  frequently  a  catarrh  of  the  stomach 
remains  behind  which  persists  for  two  or  three  days.  In 
some  instances  gastritis  sets  in,  leading  to  death.  Foreign 
body  pneumonia  is  an  occasional  complication  due  to 
aspiration  after  belching  or  vomiting.  Some  patients  die  of 
suffocation,  but  more  commonly  the  condition  leads  to 
rupture  of  the  stomach. 

Treatment. — The  only  safe  method  of  treating  this  disorder 
is  to  use  the  stomach-tube,  which  permits  the  imprisoned 
gas  to  escape,  bringing  with  it  large  quantities  of  the  gastric 
contents.  The  stomach  may  then  be  washed  out  (lavage) 
by  repeated  injections  of  lukewarm  water  to  which  creolin 
has  been  added,  siphoning  out  as  much  as  possible  after  each 
injection.  If  applied  early  this  method  w^ill  yield  to  healing 
in  nearly  100  per  cent,  in  cases  of  primary  dilatation  and  50 
to  75  per  cent,  of  secondary  dilatation.  The  use  of  mild 
laxatives  such  as  salts,  aloes,  etc.,  are  rarely  indicated  and 
are  effective  onlv  in  mihl  cases.     Barium  chlorid,  arecalin 


106       DISEASES  OF   THE  STOMACH   A.\D  BOWELS 

and  eserin  are  dangerous  in  tluit  tlioy  may  cause  rujjture  of 
the  stomach. 

Simple  Impaction  of  the  Intestines. — Definition.  Siinjjle 
impaction  of  the  bowel  (obstipation)  consists  in  an  accumula- 
tion of  feces  which  obstruct  the  lumen  of  the  bowel.  After 
a  time  the  bowel  surrounding  the  impacted  mass  loses  its 
tonicity,  dilates  and  becomes  paralyzed. 

Occurrence. — Simple  impactions  are  very  frequent  in 
horses.  Accortling  to  the  records  of  the  Berlin  Clinics 
75  per  cent,  of  the  cases  of  colic  are  due  to  this  cause.  The 
frequency  of  this  disorder,  however,  varies  with  the  kind  of 
food  and  manner  of  feeding,  so  that  these  figiu^es  do  not  ajjply 
to  all  parts  of  the  world.  For  instance,  in  Budapest  the 
statistics  show  a  much  lower  prevalency  (6  to  20  per 
cent.). 

Etiology. — The  exciting  causes  of  this  form  of  colic  are  tlue 
to  feeding  food  rich  in  cellulose  and  wood  fiber,  the  character 
of  this  type  of  food  requiring  that  large  quantities  be  ingested 
to  supply  nutrition.  Straw,  chaff,  corn  fodder,  clover  or 
alfalfa  which  is  not  young  and  tender  are  therefore  causes. 
Overfeeding  any  sort  of  food  may  have  a  like  effect.  Foods 
which  contain  a  large  amount  of  mineral  matter  or  earth, 
sand,  etc.,  often  lead  to  impaction  (bran,  barlev,  swamp 
hay). 

Horses  suffering  from  chronic  gastro-intestinal  catarrli, 
and  those  with  diseased  teeth  preventing  proper  masti- 
cation are  commonly  victims.  Old  and  very  fat  horses  which 
are  not  exercised  sufficiently  are  predisposed. 

Impaction  may  also  be  secondary  to  i)athological  conditions 
of  the  bowel  (dilatation  of  the  cecum,  stenosis  of  the  ileum, 
paralysis  of  the  rectum,  enteroliths,  worm  parasites  and 
embolism). 

Forms. — From  the  standpoint  of  diagnosis  two  forms  of 
simple  im])acti()n  are  distinguished: 
Impaction   of    the    small    bowel. 
Impaction  of  the  large  bowel. 

Impaction  of  the  Small  Bowel. — Diagnosis. — The 
l)rincipal  symptoms  of  this  form  of  impaction  are  the  sudden- 
ness of  the  attack   of  colic   which   appears  usually   a    few 


SO-CALLED  COLICS  OF  THE  HORSE  107 

hours  after  feeding.  The  pain  is  usually  quite  marked,  the 
patient  often  assuming  the  attitude  of  the  male  horse  when 
urinating.  The  peristalsis  of  the  left  side  is  suppressed  and 
defecation  ceases.  Rectal  examination  usually  gives  negative 
results.  In  small  horses,  however,  an  examiner  with  a  long 
arm  may  palpate  the  ileum  at  its  union  with  the  cecum,  as  a 
smooth,  cylindrical,  firm  mass  about  the  size  of  an  arm 
located  to  the  right  of  the  spinal  column  and  extending  from 
above  obliquely  downward  and  backward  toward  the  cecum. 
The  size  of  the  bowel  and  the  absence  of  bands  indicate  that 
it  is  the  small  and  not  the  large  intestine.  If  the  duodenum 
is  impacted,  it  may  be  felt  where  it  crosses  the  abdominal 
cavity  from  right  to  left  just  in  front  of  the  anterior  root 
of  the  mesentery.  It  is  attached  to  the  roof  of  the  cavity 
by  a  short  mesentery. 

The  pulse,  temperature  and  conjunctiva  are  usually 
normal  in  the  early  stages  (contrary  to  volvulus). 

Course. — Fresh  cases  if  properly  treated  usually  recover 
in  three  to  six  hours.  Attacks  lasting  longer  should  be 
looked  upon  less  favorably.  The  colic  in  these  instances 
may  continue  for  several  days,  the  patient  showing  inter- 
mittent pain  which  occurs  following  feeding.  The  pulse 
becomes  very  rapid,  the  temperature  feverish  and  the 
conjunctiva  cyanotic.  Death  may  also  result  from  ensuing 
volvulus  which  is  fatal  in  eight  to  twelve  hours,  intestinal 
sepsis  or  enteritis. 

Prognosis. — The  prognosis  in  impaction  of  the  small 
intestine  is  generally  good.  Not  over  5  per  cent,  of  the 
cases  die. 

Treatment. — In  the  early  stages  a  subcutaneous  injection 
of  arecalin  (^  gr.)  which  may  be  followed,  if  the  results  are 
not  satisfactory,  by  a  hypodermic  of  eserin  (^  gr.).  Usually 
the  administration  of  these  drugs  is  followed  in  from  thirty 
minutes  to  one  hour  by  defecation  and  recovery  in  three 
to  six  hours.  If  the  condition  has  been  neglected  or  the  action 
of  arecalin  and  eserin  unsatisfactory,  aloes  (5j)  may  be 
administered.  Peristalsis  may  be  further  stimulated  by 
infusions  of  water  into  the  rectum,  massage  of  the  impacted 
bowel  through  the  rectum,  and  moderate  exercise.     In  pro- 


lOS       DISEASES  OF   THE  STOMACH  AXD  BOWELS 

longed  attacks  lasting  several  days  the  patient  should  be 
muzzled  to  prevent  feeding. 

If  secondary  distention  of  the  stomach  occur,  treat  as 
in  gastric  dilatation.  It  may  be  necessary  to  use  the  tube 
repeatedly  to  prevent  rupture. 

Impaction  of  the  Large  Bowel. — I^sually  the  impaction 
occurs  in  the  cecum,  pelvic  fiexure  of  the  colon  or  at  the 
termination  of  the  right  upper  colon.  Occasionally  the 
rectum  is  impacted   (pregnant  mares). 

Impaction  of  the  Cecum. — The  causes  of  cecal  impaction 
are  practically  the  same  as  those  of  the  small  bowel.  I'snally 
when  the  cecum  becomes  imi)acted  it  is  due  to  an  organic 
change  in  the  wall  of  the  bowel  which  imdergoes  gradual 
dilatation  with  thickening.  Eventually,  the  walls  of  the 
cecum  lose  their  normal  tonicity  and  paralysis  develops 
predisi)osing  to  impactions.  As  a  result  intermittent  attacks 
of  chronic  colic  occur  which  generally  lead  to  obstinate 
constipation  and  eventually  to  toxemia,  enteritis,  rupture 
and  death. 

Diagnosis. — An  accurate  diagnosis  of  cecal  imj)acti()n  can 
be  made  only  by  rectal  examination.  In  the  right  ui)per 
flank  region  one  can  determine  a  swelling  of  about  the 
size  of  a  human  head.  The  enlargement  is  round,  surface 
smooth  and  is  not  sensitive.  Sometimes  the  bands  of  the 
cecum  may  be  felt.  The  consistency  will  vary  from  quite 
soft,  doughy  (retaining  finger  im])rints)  to  firm  or  hard.  The 
fixed  position  of  the  enlargement,  its  size  and  location  in  the 
upper  right  region  of  the  flank  make  the  diagnosis  not 
difficult.  Error  would  l)e  ])ossible  only  in  case  there  was 
impaction  with  displacement  of  the  left  lower  colon,  the 
bowel  extending  from  the  left  to  the  right  side  of  the 
abdominal  cavity.  The  impacted  left  lower  colon,  however, 
usually  occupies  the  right  lower  region  of  the  flank  and 
hugs  rather  closely  the  median  line.  The  sha])e  of  the 
impacted  mass  is,  furthermore,  elongated  and,  finally,  the 
base  of  the  cecum  can  be  felt  in  situ. 

Prognosis. — In  early  cases  pro])er  treatment  usually  pro- 
duces healing.  However,  cecal  impaction  in  the  nature  of 
things  tends  to  become  chronic,  the  i)atient  suffering  from 


SO-CALLED  COLICS  OF   THE  HORSE  109 

time  to  time  with  periodical  attacks  of  pain  the  condition 
finally  leading  to  rupture  and  death. 

Treatment. — Arecalin  (|  gr.)  combined  with  aloes  (§j)  is 
most  effective.  In  prolonged  attacks  this  treatment  may 
be  repeated.  As  an  auxiliary  the  use  of  rectal  infusions, 
massage  (via  rectum)  and  light  exercise  are  helpful.  In 
case  the  cecum  bloats  the  trocar  may  be  used. 

Impactions  of  the  Colon. — Impactions  of  the  colon 
usually  occur  either  (a)  in  the  left  layers  including  the 
jielvic  flexure  or  (h)  in  the  terminal  portion  of  the  right 
upper  colon. 

(a)  Impaction  of  the  left  layer  of  the  colon.  When  the 
left  lower  layer  is  impacted,  on  rectal  examination  may  be 
felt  a  cylindrical  mass  usually  just  in  front  of  the  pelvic 
inlet  or  more  rarely  protruding  into  the  pelvic  cavity.  The 
left  lower  layer  is  distinguished  by  its  bands  and  pockets, 
the  left  upper  layer  by  the  absence  of  bands,  its  caliber,  and 
direction  in  practically  a  straight  line  forward.  The  greater 
diameter  and  straight  direction  of  the  left  upper  colon 
differentiates  it  from  the  smaller,  tortuous  loops  of  small 
bowel. 

(6)  Impaction  of  the  right  upper  colon.  The  impacted 
mass  is  imprisoned  in  the  "stomach-like"  dilatation  of  this 
bowel,  beginning  at  the  funnel-shaped  termination  and 
extending  forward  and  including  the  widest  diameter  of  the 
bowel.  Except  in  small  horses  the  results  of  rectal  examina- 
tions are  almost  negative.  When  the  impaction  may  be 
felt  it  is  distinguished  by  its  location  anterior  to  the  cecum, 
slightly  to  the  right  of  the  median  line.  The  mass  is  some- 
what round,  firm,  often  covered  by  the  root  of  the  mesentery, 
and  tends  to  move  synchronous  with  respirations. 

In  case  the  result  of  the  rectal  examination  is  negative, 
it  would  be  impossible  to  distinguish  between  impaction  of 
the  right  upper  colon  and  that  of  the  small  bowel.  In  the 
last  stages,  if  quantities  of  gas  accumulate  in  the  left  layers 
of  the  colon  the  condition  may  be  assumed;  if,  on  the  other 
hand,  the  gaseous  distention  is  confined  to  the  small  bowel 
an  impaction  of  this  is  probable.  The  general  condition 
of  the  patient  in  impaction  of  the  colon  remains  for  quite  a 


110       DISEASES  OF   THE  STOMACH   AM)  BOWELS 

tiiiK'  good.  The  pulse  and  eonjunctiva  usually  are  about 
normal.  Obviously  when  enteritis,  septic  intoxication  or 
rupture  occur  the  <rencral  condition  becomes  bad. 

Impaction  Complicated  with  Abnormal  Displacement. — 
Forms. — The  following  abnormal  displacements  of  the  bowel 
have  been  noted:  Torsion  of  the  large  bowel  (colon  and 
cecum),  volvulus  of  the  small  bowel,  intussusception  of  the 
small  bowel,  incarceration  of  the  bowel  (inguinal  canal, 
ei)iploic  foramen,  rents  in  the  diaphragm,  omentum,  mesen- 
tery, etc.),  and  strangulation  of  the  intestines  from  tumors. 

All  of  these  pathological  displacements  lead  to  a  sudden 
occlusion  of  the  bowel  and  fatal  colic.  They  constitute 
about  5  per  cent,  of  all  colic  cases.  Of  great  practical  impor- 
tance are: 

(a)   Displacement  of  large  bowel. 
(fe)   Displacement  of  small  bowel. 

Displacement  of  Large  Bowel. — ]\Iost  commonly  this 
consists  in  a  rotation  (torsion)  of  the  left  colons  around 
their  long  axes.  On  account  of  their  free  position  in  the 
abdominal  cavity,  contrary  to  the  colons  on  the  right  side, 
a  certain  predisposition  to  abnormal  displacement  is  present. 

Etiology. — The  exciting  causes  are  usually  ])rimary  im- 
pactions behind  the  point  of  torsion.  Therefore  an  impac- 
tion of  the  upper  may  lead  to  torsion  of  the  lower  colons, 
or  an  impaction  of  the  lower  to  torsion  of  the  upper  colons. 
Impaction  may  be  determined  in  at  least  SO  ])er  cent,  of  all 
cases  of  displacement  of  the  large  bowel.  Impaction  induces 
in  the  bowel  which  is  in  front  of  it  a  violent  antiperistaltic 
movement  whereby  secondarily  a  torsion  follows.  In  other 
instances  })aralysis  of  the  bowels  due  to  embolism  is  the 
cause.  Very  rarely  rolling  in  horses  suffering  from  colic 
may  lead  to  displacement. 

Diagnosis. — A  correct  diagnosis  can  be  arrived  at  only 
through  rectal  examination.  Very  important  in  this  regard 
is  the  course  of  the  bands  of  the  left  lower  colon.  In  place 
of  their  normal  straight  course  the  bands  will  be  found 
bent  spirally  to  the  right  or  to  the  left.  The  twist  is  always 
opposite  to  the  direction  of  the  bands.  For  instance,  the 
common  twist  of  the  left  layers  of  the  colon  is  to  the  right; 


SO-CALLED  COLICS  OF   THE  HORSE  \  1  1 

the  bands  are  twisted  spirally  toward  the  left  in  this  con- 
dition. Besides  the  resnlt  obtained  from  rectal  examination 
it  will  be  noted  that  the  general  condition  of  the  patient  is 
rapidly  becoming  serious  which  is  usually  indicated  in  one 
or  two  hours  by  the  change  in  the  pulse,  peristalsis,  tempera- 
ture and  conjunctiva.  There  is,  further,  profuse  sweating, 
great  prostration,  collapse,  etc. 

Prognosis. — If  the  torsion  is  not  soon  removed  death  will 
result  in  six  to  twelve  hours. 

Displacement  of  the  Small  Bowel  (Vohuhts). — 
Etiology. — Usually  a  primary  impaction  of  a  part  of  the 
bowel  behind  the  volvulus  is  the  cause  of  change  in  position 
The  impaction  may  be  either  in  the  small  or  large  bowel. 
Volvulus  of  the  jejunum  is  commonly  produced  by  impaction 
of  the  ileum  (stenosis).  As  in  the  case  of  the  large  bowel 
a  violent  antiperistaltic  movement  of  the  bowel  lying  in 
front  of  the  impaction  favors  torsion. 

Diagnosis. — Contrary  to  torsion  of  the  large  bowel  vol- 
vulus can  rarely  be  determined  per  rectum.  A  diagnosis 
is  usually  only  possible  by  way  of  exclusion  and  is  as  such 
a  probable  one.  If  on  rectal  exploration  no  change  can  be 
found  in  the  layers  of  the  large  intestine  and  the  condition 
of  the  patient  is  rapidly  growing  bad,  the  probability  of  a 
volvulus  is  great.  In  some  cases  the  bloating  of  the  small 
intestine,  which  may  be  determined  per  rectum,  point  to 
volvulus. 

Prognosis. — The  prognosis  is  bad.  Death  usually  results 
in  eight  to  twelve  hours. 

Treatment. — Treatment,  as  a  rule,  is  without  avail. 
Attempts  to  relieve  the  animal  by  a  laparotomy  have  not 
proven  to  be  feasible. 

Embolic  Colic. — Definition. — By  the  term  embolic  or 
thrombo-embolic  colic  we  understand  intestinal  pain  from 
a  disorder  of  the  intestines  due  to  the  presence  of  a  worm 
aneurysm  in  the  anterior  mesenteric  artery.  The  cause  of  the 
worm  aneurysm  is  the  larva  of  the  Strongylus  armatus, 
the  armed  palisade-worm.  The  adult  worm  lives  in  the 
large  bowel  and  the  eggs  are  discharged  with  the  feces.  In 
the  soil  or  stable  floor  the  larvae  are  hatched  and  are  taken 


112       D/SI'JASES   OF    TIU<:   STOMACH   AM)   BOWELS 

up  hy  healthy  horses  (eoltsj  with  the  bedding  or  grass  of  the 
pasture  and  with  the  drinking  water.  From  the  bowel  the 
larviv  pass  into  the  veins  of  the  mueous  membrane  of  the 
intestines,  reach  the  right  heart  and,  after  passing  through 
the  lungs,  the  arterial  circulation.  According  to  some 
authorities  they  wander  direct  from  the  intestines  between 
the  leaves  of  the  mesentery  to  the  anterior  mesenteric  trunk. 
There  are  found  ])rincipally  in  this  trunk  or  its  principal 
branch,  the  ileocolic  artery.  By  irritating  the  inner 
w  all  of  the  artery  they  produce  a  chronic  endarteritis.  The 
results  of  the  inflammation  of  the  artery  are:  thrombosis, 
dilatation  and  calcification  of  the  arterial  wall  (aneurysm). 

Notwithstanding  that  nearly  all  horses  (about  90  per  cent.) 
suH'er  from  this  aneurysm,  embolic  colic  occurs  in  only  about 
5  i)er  cent. 

Pathogeneses. — The  worm  aneurysm  of  the  anterior 
mesenteric  artery  ])r()duces  disorder  of  the  bowel  in  three 
different  ways:  {a)  detached  fragments  (embolic)  of  the 
thrombus  may  reach  the  peripheral  intestinal  arteries.  (6) 
The  thrombus  itself  may  become  prolongated  into  branches 
of  the  artery,  (c)  The  thrombus  may  in  rare  instances 
completely  obstruct  the  lumen  of  the  mesenteric  trunk. 
In  all  three  of  these  cases,  de])en(ling  upon  whether  or  not 
the  collateral  circulation  suffices,  there  results  anemia, 
hemorrhagic  infarction,  and  ultimately  a  necrosis  of  the 
mucosa  of  the  bowel.  On  necropsy,  therefore,  we  find 
princii)ally  the  symptoms  of  a  hemorrhagic  inflammation 
of  the  l)owels  with  necrosis  and  at  the  same  time  occlusion 
or  thrombosis  of  the  afferent  and  peripheral  arterial  branches. 

Symptoms. — The  attack  of  colic  usually  begins  suddenly, 
mostly  during  work.  In  mild  cases  the  attack  resembles 
somewhat  spasmodic  colic  in  that  the  pain  is  intermittent. 
On  rectal  examination  everything  seems  intact  provided  there 
is  no  disi)lacement  secondary  to  the  thrombosis;  or  we  may 
be  able  to  feel  fremitis  over  the  region  of  the  anterior  mesen- 
teric artery.  In  many  instances  the  thrond)us  can  be 
l)alpated  ])er  rectum.  In  the  severe  type  bloating  is  an 
ordinary  symptom.  This  form  of  colic  tends  to  hang  on 
with  periods  of  remission  for  one  or  two  weeks,  although  it 


SO-CALLED  COLICS  OF   THE  HORSE  113 

usually  lasts  but  a  few  liours.  It  is  frequently  attended  by 
fever  and  sometimes  the  stools  are  blood-stained.  It  is  very 
apt  to  lead  to  enteritis,  rupture  of  the  stomach  or  bowel, 
septic  intoxication  or  peritonitis.  Embolic  colic  is  a  frequent 
cause  of  impaction  especially  impaction,  complicated  with 
displacement. 

Diagnosis. — In  the  living  horse  the  diagnosis  of  embolic 
colic  is  always  a  probable  one.  It  may  be  suspected  when 
without  apparent  cause  repeated  attacks  of  colic  occur  and 
more  especially  if  the  feces  contain  blood. 

Treatment. — The  treatment  is  the  same  as  in  simple 
impaction.  Atoxyl  (§iij)  of  a  3  per  cent,  solution  given 
intravenously  are  said  to  eradicate  the  strongylus. 

Spasmodic  Colic. — Definition. — By  spasmodic  colic  we 
understand  a  rather  severe  attack  of  abdominal  pain  due  to 
spasmodic  contractions  of  the  bowel,  probably  superinduced 
by  intestinal  catarrh.  It  is  characterized  clinically,  in  contra- 
distinction to  impaction  colic,  by  diarrhea,  rapid  course, 
intermittent  pain  and  favorable  termination. 

Treatment. — This  form  of  colic  should  be  treated  with 
drugs  which  allay  pain  such  as  morphin  (gr.  iij-vj) ,  chloral 
(5j).  Arecalin,  and  especially  eserin  and  barium  chlorid, 
are  contra-indicated.  Warm  applications  to  the  belly  are 
valuable. 

Worm  Colic. — Intestinal  Parasites. — The  intestinal  para- 
sites of  the  horse  (spool-worms,  tapeworms,  palisade-worms), 
notwithstanding  their  frequency,  rarely  produce  colic.  How- 
ever, if  present  in  large  numbers  they  may  (1)  obstruct  the 
bowel,  producing  simple  impaction,  (2)  mechanically  irritate 
the  mucous  membrane,  inducing  enteritis  or  (3)  by  emigrat- 
ing into  the  abdominal  cavity  lead  to  peritonitis.  In  this 
connection  the  following  parasites  are  important: 

Ascaris  megalocephala,  the  spool-worm  of  the  horse.  Pro- 
duces obstruction,  perforation  of  the  bowel  at  the  attachment 
of  the  mesentery,  worm  cysts  and  peritonitis. 

Taenia  plicata,  perfolia  and  mamillana,  the  tapeworms  of 
the  horse.     Produce  obstruction  and  perforation. 

Strongylus  armatus  and  tetracanthus,  the  adult  palisade- 
worms  of  the  horse.    They  produce  hemorrhagic  enteritis. 


114       DISEASES  OF   TIU<:  STOMACH   AM)   BOWELS 

Oxyiiris  curviila,  tlie  wliip-worin  of  the  horse,  wliich 
l)ro(hi('e.s  proctitis. 

The  hirvse  of  Gastropliiluseciui  and  ])eeoruin  rarely  j)r()(luee 
colic.  In  exceptional  cases  in  colts  they  may  induce  traumatic 
gastritis  or,  by  perforating;  the  stomach  wall,  peritonitis. 

Treaimcui. — Through  the  use  of  purges  alone  intestinal 
worms  cannot  always  be  removed.^  The  most  valuable 
agent  for  their  removal  in  horses  is  tartar  emetic  (5ij  to 
5ss)  daily;  given  in  drinking  water  two  or  three  times. 
Besides  arecanut  (5ii.i)i  arsenic  (gr.  xv-xxx  in  form  of 
boli),  santonin  (oii^"^)  and  turpentine  oil  (§iss-5iij)  may  be 
used.  For  gastrus  larvae  in  the  stomach  bisulphide  of  carbon 
(5iiss)  given  at  night  in  capsules,  four  capsules  given  one 
hour  ai)art.     Follow  with  linseed  oil  (Oj). 

Flatulent  Colic. —  In  some  cases  of  simple  impaction  or  in 
impaction  complicated  with  displacement  an  abnormal 
fermentation  of  the  bow'el  contents  results.  The  gas  (CO2, 
CH4,  H,  air)  formed  leads  to  a  distention  of  the  abdominal 
wall.     It  is  more  rarely  due  to  "wind  sucking." 

Symptoms. — The  sym})toms  are  those  of  simple  or  com])li- 
cated  im])action  with  great  distention  of  the  abdominal  wall, 
and  from  compression  of  the  diaphragm,  severe  dyspnea. 

Treatment. — The  treatment  consists  in  using  the  trocar 
either  through  the  side  (cecum)  or  more  rarely  through  the 
rectum.  If  the  stomach  is  bloated  the  stomach-tube  should 
be  used. 

GASTRO-INTESTINAL  CATARRH  OF  THE  OX. 

Indigestion  of  Cattle. 

Definition. — Gastro-intestinal  catarrh  of  the  ox  is  an  inflam- 
mation of  the  mucous  membrane  of  the  stomach  and  bowels. 
As  the  superficial  layers  of  the  mucosa  of  the  rumen  are 
provided  with  a  horny  epithelium  and  the  organ  is  probably 
glandless,  it  offers  remarkable  resistance  to  the  causes  of 
inflammation.    Most  of  the  disturbances  of  the  rumen  are 


'According  to   Udall   and   Alhrerht    aloes   alone   is   an   etfieient    agent   to 
expel  intestinal  worms  in  horses. 


GASTRO-IXTESTINAL  CATARRH  OF   THE  OX       115 

therefore  functional.  In  the  other  compartments  of  the 
stomach,  especially  the  abomasum,  this  is  less  true  and  in 
them  catarrh  is  readily  noted  on  necropsy.  Obviously  when 
the  function  of  the  rumen  is  impaired  the  other  compart- 
ments must  suffer,  and  riee  versa  catarrhs  of  the  reticulum, 
omasum  or  abomasum  will  affect  the  functions  of  the  rumen. 

Occurrence. — Gastro-intestinal  catarrh  is  one  of  the  most 
common  non-infectious  diseases  of  cattle,  particularly 
stable-fed  animals.  Those  on  pasture  are  by  no  means 
exempt,  especially  during  periods  of  drought,  extreme  rain 
or  when  the  water  supply  is  insufficient  or  bad. 

Etiology.— The  most  potent  causes  of  gastro-intestinal 
catarrh  are  foods  and  feeding.  Foods  which  are  too  woody 
(chaff,  dried  coarse  grasses,  shrubs,  underbrush,  tree  tops), 
improperly  harvested  forage  (cut  too  green,  fermenting  clover, 
over-ripe  hay,  etc.),  spoiled  food  (mouldy  meal,  decayed 
vegetables),  otherwise  damaged  food  (frozen  grass  or  silage, 
frosted  beets),  and  finally  feeding  kitchen  offal  in  the  form 
of  swill,  etc. 

The  injudicious  feeding  of  good  food  can  produce  gastro- 
intestinal catarrh  as,  for  instance,  overfeeding  or  the  sudden 
change  from  a  well-balanced  to  a  very  narrow  ration.  \Yith- 
holding  roughage  is  also  a  cause.  Allowing  a  full  drink  of 
cold  water  on  a  full  stomach  is  harmful  in  this  regard.  ( ^attle 
may  overload  the  stomach  by  getting  loose  and  gaining  access 
to  the  grain  bins  or  fields  of  growing  grain. 

Foreign  bodies  (nails,  screws,  pieces  of  tin,  sand,  hair 
balls,  stones)  so  common  in  the  reticulum  are  causes.  Patho- 
logical conditions  of  the  gullet  (compression  from  enlarged 
mediastinal  lymph  glands,  diverticuli) ,  stomach  (adhesions, 
abscess,  actinomycomas,  sarcomas,  lymphomas  in  wall  of 
rumen  and  bowels,  "nodule  disease,"  Johne's  disease, 
tuberculosis,  tumors).  Psychic  influences  (removing  young 
calf,  strange  environment)  in  nervous  cattle  may  produce 
temporary  digestive  disturbances. 

Symptoms.— The   symptoms   of   gastro-intestinal   catarrh 

are:  i    •        i 

G'a^^ric— Suppressed  rumination;  the  cud  not  benig  chewed 
at  all  or  with  little  vigor.    Impaired  appetite;  often  no  food 


IK)       DISEASES  OF   THE  SrOMACII  AXD  BOWELS 

he'uVf^  taken  or  only  in  small  quantities.  Quite  often  foamy 
saliva  ap})ears  at  the  commissures  of  the  mouth.  The 
muzzle  usually  becomes  dry  and  the  nostril  openinjjs  are  not 
cleaned  by  the  tongue.  Eructations  of  gas  from  the  gullet 
(l)elching)  is  a  common  symptom.  Occasionally  a  regurgita- 
tion (not  true  vomiting)  of  rumen  contents  through  the 
mouth  is  noted.  The  hollow  of  the  left  flank  is  distended 
with  gas,  the  })aunch  m<)\ements  either  cease  or  are  very 
feeble  and  on  ])alpation  (o\er  flank  or  through  rectum)  the 
food  in  the  rumen  feels  firmer  and  retains  finger  imprints 
longer  than  in  health.  In  some  cases  palpation  of  the  left 
flank  distresses  the  patient. 

Intestinal. — Occasionally  colicy  i)ains  are  manifested  by  the 
animal  switching  its  tail  and  kicking  against  the  abdomen 
with  its  hind  limbs.  Rolling,  as  in  the  horse,  is  rarely  ob- 
served. The  bowels  are  generally  constipated,  the  feces  black, 
hard  and  dry,  sometimes  covered  with  blood-stained  mucus 
and  i)assed  in  the  form  of  fist-sized  balls.  If  the  patient  has 
been  fed  on  very  succulent  food  (beets,  beet  tops)  there  may 
be  diarrhea.  In  chronic  cases  the  constipation  may  be 
interrupted  by  diarrhea,  the  feces  having  a  sour,  fetid  odor 
and  occasionally  admixed  with  mucus,  shreds  of  fibrin  and 
blood.  IVristalsis  is  li\ely  when  diarrhea  is  ])resent,  suj)- 
pressed  during  constipation. 

General. — In  mild,  acute  cases  there  is  little  general 
di.sturbance  beyond  a  certain  degree  of  languor  or  restlessness. 
When  the  indigestion  ])ersists  for  several  days  the  ])atient 
may  be  distressed,  standing  with  all  four  feet  drawn  together, 
its  head  forced  into  a  corner  or  against  the  stanchion,  the 
teeth  are  gnashed  frequently,  the  back  is  arched,  the  muzzle 
is  dry  and  the  eyes  retracted.  Fever  is  ])rcsent,  beginning 
about  the  third  day.  The  tem])crature  is  rarely  high  (104.5° 
F.).  The  pul.se  becomes  rapid  and  weak.  If  bloating  or 
great  impaction  of  the  rumen  are  present,  dyspnea  exists.  In 
chronic  cases  the  general  condition  grows  contiiuiously  worse, 
the  patient  becoming  anemic,  emaciated,  even  cachectic  and 
eventually  dies  of  inanition. 

Diagnosis.—  The  disease  should  be  distinguished  from  acute 
bloat  (marked  distention,  dyspnea,  sudden  appearance,  short 


GASTRO-INTESTINAL  CATARRH  OF  THE  OX      117 

duration),  traumatic  indigestion  (pain  over  region  of  dia- 
phragm, evidence  of  peritonitis,  heart  symptoms),  and  such 
other  diseases  to  which  catarrh  of  the  stomach  and  bowel 
is  secondary  (Johne's  disease,  tuberculosis,  tumors,  adhesions, 
chronic  metritis,  i)yelonepln'itis,  rabies). 

Course. — INIild  acute  attacks  usually  last  only  three  or 
four  days.  More  severe  cases  persist  for  one  or  two  weeks, 
recovery  following  a  copious  discharge  of  feces.  Or  death 
from  gastric  enteritis  may  ensue.  Chronic  cases  hang  on,  as 
a  rule,  for  several  weeks.  There  may  be  exacerbations  and 
remissions  but  generally  the  disease  makes  persistent  progress 
toward  a  fatal  termination. 

Prognosis. — The  prognosis  depends  upon  the  possibility 
of  removing  the  cause  and  the  severity  of  the  case.  If  the 
rumen  is  filled  with  indigestible  food  which  is  solidly  impacted 
or  if  serious  inflammation  of  the  walls  of  the  digestive  tract 
has  developed,  the  prognosis  is  grave.  While  acute  cases, 
provided  gastro-enteritis  does  not  set  in,  usually  recover, 
chronic  cases  usually  die. 

Treatment. — The  task  confronting  the  practitioner  is  to : 

1.  Promote  the  movements  of  the  paunch  and  stimulate 
rumination. 

2.  To  arrest  the  fermentation  of  the  stagnant  food  masses. 

3.  To  relieve  the  resulting  impaction  of  the  omasum  and 
the  constipation  of  the  bowels. 

Hygienic. — Food  should  be  withheld  or  restricted  (muzzle) 
for  a  few  days  in  acute  cases.  Kneading  the  walls  of  the 
abdomen  five  to  ten  minutes  every  three  hours  or  three  times 
daily  is  helpful.  Keep  salt  and  plenty  of  water  accessible. 
If  food  is  given  it  should  be  easily  digestable  and  laxative 
(fresh  grass,  bran  gruels,  fine  hay,  root  crops). 

Medicinal. — To  stimulate  paunch  movements  and  to 
relieve  constipation  laxative  drugs  are  indicated.  The  rule 
should  be  to  employ  the  milder  drugs  of  this  sort  first;  at 
any  rate,  drastic  purges  should  be  avoided.  As  physics, 
oil  and  salts  do  little  good  in  obstinate  cases.  In  mild  attacks 
Glauber  salts  (5  xxiv)  and  raw  linseed  oil  (Oiss)  are  effective. 
More  active  is  castor  oil  (5  xxiv)  in  equal  volume  of  warm 
water.     Ether  (5ij)  may  be  added  to  the  mixture.     The 


lis      DISEASES  OF   THE  STOMACH  AXD  DOWELS 

tartrate  of  eseridrin  is  roconiinciKlcd  (I^ — Eseridrini'  <;r. 
iij,  acid,  tartar  j;r.  iss,  aqu.  dost,  o^j-  ^F.  D.  S.  Subciita- 
neoiisly).  The  suli)hate  of  veratriii  (1  to  oO  in  water — dose 
5ij  per  oroii),  or  barium  chlorid  (5ij  l)er  orem).  Impaction 
of  the  ])aunch  may  be  relieved  l)y  direct  infusions  into  tlie 
orjjan  tlirouj^li  a  trocar  which  has  been  inserted  in  the  hoHow 
of  the  Hank.  The  water  sliould  be  tei)id  and  may  contain 
creoUn.  Several  ti;alk)ns  may  be  allowed  to  flow  in  at  a  time 
and  the  treatment  repeated  daily.  By  placing  a  rail,  held 
at  each  end  by  a  person,  mider  the  abdominal  wall,  and 
working  it  up  and  down,  the  contents  of  the"  rumen  may  be 
readily  mixed  with  the  water  infusion.  In  case  this  does  not 
afford  relief,  rumenotomy  shoukl  be  performed. 

To  arrest  gastric  fermentation  and  act  as  a  tonic  hydro- 
chloric acid  may  be  given  (5v  diluted  in  water  1  to  250)  to 
■which  i)epsin  (oiiss)  may  be  added.  Creolin  (5j)  may  be 
used  to  arrest  fermentation. 

The  appetite  may  be  stimulated,  once  the  patient  begins 
to  eat,  by  bitter  aromatic  herbs  (I^ — Calamus,  gentian, 
peppermint,  caraway  ail  5,1-  ^I-  r)-  i^-  Tablespoonful  three 
times  daily). 

The  animal  should  be  brought  to  full  feed  gradually. 
I^sually  one  should  wait  until  rumination  rea])i)ears  and  begin 
with  one-fourth  to  one-half  rations.  The  drinking  water 
should  not  be  too  cold. 

GASTRO-INTESTINAL  CATARRH  OF  SUCKLINGS. 

Scours  of  Sicklings.    Sporadic  Dysentery. 

Definition. — A  catarrh  of  the  mucosa  of  the  stomach  and 
bowels  of  calves,  lambs,  or  foals.  Clinically,  it  is  a  diarrhea 
usually  occurring  in  the  first  few  days  (two  to  ten)  after  birth. 

Occurrence. — A  very  common  disease  among  sucklings, 
es])e(ially  those  which  are  "raised  by  hand,"  or  where  the 
young  animal  is  permitted  to  suck  its  dam  only  at  long 
inter  vals. 

Etiology. — The  cause  of  gastro-intestinal  catarrh  is  un- 
doul)tcdly  bacterial.    Probably  the  Bacillus  coli  communis  is 

'  Vory  oxiJOiisivi'!     Arocaliii  is  :i  good  s\ih.stituto. 


GASTRO-INTESTINAL    CATARRH   OF   SUCKLINGS     119 

an  important  factor.  While  this  germ  is  regularly  present  in 
the  bowels  of  sucklings,  and  usually  does  no  harm,  once  the 
resistance  of  its  host  is  lowered  by  error  of  diet,  exposure, 
etc.,  it  can  become  pathogenic.  Other  intestinal  bacteria 
may  assume  a  similar  role.  Predisposing  causes  are:  (a) 
weaning  too  early;  (b)  feeding  boiled  milk  (destroys  ferments 
in  milk  which  aid  digestion),  or  substitutes  (flour,  linseed, 
cotton  seed)  for  milk;  (c)  feeding  spoiled,  contaminated  (sour, 
putrid)  milk  out  of  filthy  vessels;  (d)  overfeeding,  allowing 
the  hungry  suckling  to  gorge  itself  with  milk  after  too  long 
a  period  of  fasting,  as  in  the  case  with  foals  of  working  mares; 
(e)  sucking  the  diseased  udder  (various  forms  of  mastitis); 
(/)  the  eating  of  solid  foods  by  the  newborn  animal,  which  it 
is  unable  to  digest,  such  as  hay,  straw,  etc.;  (g)  preventing 
the  suckling  from  obtaining  the  colostrum,  which  removes  the 
meconium  from  the  bowel ;  (h)  refrigeration  (cold,  damp  stable) . 

Symptoms. — The  first  symptom  is  usually  refusal  to  suck 
or,  if  weaned,  to  drink  the  milk  offered.  The  little  patient 
is  languid,  depressed.  Colicky  symptoms  are  not  rare.  There 
is  often  bloating.  The  most  marked  symptom  is  diarrhea. 
The  feces  are  thin,  yellowish  or  dirty  white  in  color,  often 
foamy,  of  pungent,  sour  odor  and  voided  with  tenesmus  and 
considerable  force.  Sometimes  they  are  flocculent  (like 
buttermilk).  They  are  usually  sticky  and  adherent  to  the 
anus,  tail,  buttocks,  etc.,  which  regions  they  excoriate.  As 
the  disease  progresses  the  patient  becomes  weak  and  anemic, 
and  remains  lying  most  of  the  time.  The  eyeballs  retract, 
the  skin  feels  cool,  moist,  and  sticky,  and  a  most  disagreeable 
odor  is  emitted  from  the  body.  In  fatal  cases  toward  the 
end  the  periphery  of  the  body  grows  cold,  the  anal  sphincter 
relaxed,  and  incontinence  of  feces  follows.  Death  may  occur 
under  convulsions. 

Diagnosis. — Gastro-intestinal  catarrh  may  be  confused  with 
infectious  dysentery  of  newborn  animals.  This  latter  dis- 
ease, however,  usually  appears  earlier  (may  be  born  with  it), 
rims  a  much  more  rapid  course,  and  is  very  fatal  (80  per  cent, 
mortality). 

Course  and  Prognosis. — The  course  is  generally  favorable. 
Often,  even  after  several  days'  illness,  the  diarrhea  suddenly 


120      DISEASES  OF   THE  STOMACH  AND  BOWELS 

ceases,  tlie  appetite  returns,  and  recovery  is  rapid.  In  grave 
cases  tlie  diarrliea  may  persist  for  weeks  and  the  disease 
finally  lead  to  death  through  catarrhal  pneumonia.  The 
younger  the  animal  at  the  time  of  attack,  tlie  less  favorable 
the  ])r()gnosis. 

Treatment.^ — The  diet  should  be  restricted.  The  surround- 
ings, drinking  vessels,  etc.,  of  the  patient  should  be  made 
clean  and  sterile.  Hand-fed  calves  may  be  giAen  pasteurized 
or  formalin  milk  (1  to  2r),()00).  Lime  water  added  to  the  milk 
(3 j  to  the  quart)  is  good.  Boiled  oatmeal  is  a  ^•alual)le  addi- 
tion to  pre^'ent  bloating.  The  teats  of  the  mother  should  be 
cleansed  before  the  young  are  allowed  to  suck.  Castor  oil 
(3j)  is  a  valuable  drug  in  the  earlier  stages,  as  it  removes 
from  the  bowel  the  irritant  contents.  This  may  be  followed 
by  an  intestinal  disinfectant,  such  as  salicylic  acid  (5ss)  some- 
times combined  with  tannin  (5ss).  Calomel  (gr.  xx)  is  a 
valuable  drug  for  foals.  To  check  the  diarrhea,  opium  (5j) 
combined  with  tannin  (oj)  and  whisky  (5ij)  given  in  a  pint 
of  warm  water  is  efficient.  A  non-official  })reparation  to  check 
diarrhea  is  favorably  spoken  of.  It  is  called  "Mistura  contra 
Diarrha'um,"  and  has  the  following  formula:  I^ — ^Tinct. 
opii,  tinct.  capsica,  tinct.  rhei,  tinct.  camphor,  tinct.  menthi 
aa  5j.  ]\I.  D.  S.  Dose  5j-v.  Hertwig's  mixture  is  time 
honored.  It  is  as  follows:  I^ — Opii  gr.  v,  mag.  carb.  gr.  xv, 
pulv.  rhei  3j-  M.  D.  S.  Give  in  dilute  alcohol  §iss.  Dose 
tablespoonful  twice  daily.   In  calves  bismuth  (oj)  daily  is  good. 

On  collapse  subcutaneous  doses  of  slightly  alkaline  salt 
solution  (sodium  chlorid  O.S  per  cent.,  carbonate  of  sodium 
0.25  per  cent.)  are  beneficial.  Two  quarts  of  the  solution  are 
injected  under  the  skin  of  the  neck.  May  be  repeated  in 
two  to  five  hours.  Uectal  injections  (same  dose)  are  also 
recommendable.  Oil  of  camphor  subcutaneously  is  an  ex- 
cellent stimulant. 

GASTRO-ENTERITIS. 

Inflammation  ok  the  Stomach  and  Bowels. 

Definition. — Oastro-enteritis  is  a  symptom  rather  than  a 
disease.     It  is  a  collectixe  term  coverinsr  all  conditions  which 


GASTRO-ENTERITIS  121 

directly  or  indirectly  induce  serious  inflammations  of  the  walls 
of  the  gastro-intestinal  tract.  From  catarrh  pathologically  it 
varies  only  in  degree;  clinically  it  differs  in  the  intensity  of 
the  symptoms  and  in  the  usual  fatal  termination. 

Occurrence. — Gastro-enteritis  is  common  in  all  animals, 
occurring  as  either  a  primary  or  a  secondary  disorder. 

Forms. — From  a  pathological  standpoint,  croupous,  diph- 
theritic, hemorrhagic,  purulent,  and  phlegmonous  forms  are 
distinguished;  from  a  topographic  duodenitis,  ileitis,  typh- 
litis, colitis,  and  proctitis,  depending  upon  the  part  of  the 
bowel  tract  involved.  From  a  clinical  standpoint  the  fol- 
lowing forms  occur : 

(a)  simple,  (b)  croupous,  (r)  mycotic,  (d)  toxic. 

Simple  Gastro-enteritis. — Etiology. — The  causes  of  simple 
gastro-enteritis  are  in  a  general  way  the  same  as  those  of 
gastro-intestinal  catarrh,  but  acting  more  intensively  (see 
these).  Food  which  is  infected  with  bacteria  or  fungi  or 
damaged  by  improper  harvesting,  frost,  or  containing  poison- 
ous, irritant  weeds;  or  good  food  injudiciously  fed  may 
therefore  be  predisposing  factors.  Overexertion,  especially 
in  very  hot  weather  (horses  at  hard  work,  animals  shipped 
long  distances  by  rail,  etc.),  predisposes  by  greatly  lowering 
resistance.  Copious  draughts  of  cold  water,  the  body  being 
hot,  act  in  much  the  same  way. 

The  exciting  causes  of  gastro-enteritis  are  evidently  bac- 
terial. Probably  no  one  species,  however,  is  a  constant 
cause.  For  some  as  yet  unknown  reason  microorganisms 
which  are  regularly  found  in  the  digestive  tract  assume 
pathogenic  activity  once  the  resistance  of  the  patient  is 
reduced  by  dietary  errors,  overexertion,  extreme  heat,  etc. 
It  may  thus  be  caused  by  some  of  the  colon  bacillus  group. 
The  Bacillus  enteriditis,  the  necrosis  bacillus  and  the  pus 
bacteria  seem  to  have  been  active  in  some  cases. 

Animal  parasites  (Strongylus  tetracanthus  and  Spiroptera 
megastoma  in  horses,  and  spiroptera  strongylina  in  swine) 
are  justly  accused. 

In  the  ox  a  traumatic  gastritis  results  from  foreign  bodies 
penetrating  the  walls  of  the  stomach  (see  Traumatic  Indiges- 
tion of  the  Ox). 


122       DISEASES  OF   THE  STOMACH  AND  BOWELS 

( A'rtaiii  irritant  drugs  (aloes,  caiitliarides;  can  cause  toxic 
gastro-enteritis. 

Symptoms. — The  symptoms  of  simple  gastro-enteritis  are 
much  more  intensive  than  those  of  catarrh.  \\  hile  at  times 
they  (leveloj)  graxhially  (foHow  catarrh),  as  a  rule  the  onset  is 
sudden  (six  to  ten  hours).  The  principal  symptom  is  ab- 
dominal pain,  which  is  continuous  and  generally  severe.  Ap- 
petite for  food  is  entirely  absent,  although  water  may  be 
taken  at  frequent  intervals.  In  the  early  stages  the  bowels 
are  constipated  and  })eristalsis  suppressed.  Later  diarrhea 
sets  in;  profuse  quantities  of  miscolored,  liquid  feces  are 
voided.  Depending  upon  the  form  of  inflammation,  the  feces 
may  be  admixed  with  blood  (hemorrhagic  enteritis),  i)us 
(abscess,  purulent  enteritis),  fibrinous  masses  (fibrinous 
enteritis),  necrotic  tissue  (diphtheritic  enteritis),  and  mucus 
(proctitis) .  The  pulse  reaches  70  to  90  (in  horse)  and  becomes 
weak,  small,  and  hard  in  character.  The  mucous  membranes 
(eyelid)  grow  cyanotic  (toxemia).  The  temperature  is  ele- 
vated (104°  to  100°  F.)  and  the  type  of  fe\'er  intermittent  in 
prolonged  cases.  Toward  the  end  the  temperature  is  subnormal. 

The  general  condition  of  the  patient  is  that  of  great  })ros- 
tration.  The  body  nuiy  be  wet  with  sweat,  the  countenance 
relaxed,  eyes  staring,  legs  and  ears  cold,  and  gait  staggering. 
The  pulse  becomes  very  weak,  finally  imperceptible,  the 
mucous  membranes  grow  cyanotic,  and  toward  the  end  the 
patients  are  down  in  a  s()i)orous  condition  and  may  show 
convulsive  movements  of  the  legs. 

Diagnosis. — Sim})le  gastro-enteritis  is  characterized  by  its 
sudden  onset,  rapid,  fatal  course,  and  the  gravity  of  its 
symptoms  of  abdominal  pain  (colic),  tender  "tucked-up" 
abdomen,  obstinate  diarrhea,  weak,  wiry,  freciuent  ])nlsc, 
fever,  and  in  the  last  stages  the  marked  mental  dei>ression 
(sometimes  excitement)  and  exhaustion.  It  might  be  con- 
fused with  certain  poisonings  (toxic  gastro-enteritis).  The 
history  of  the  case,  luunber  of  animals  afl'ected,  and  the  special 
sym])t()ms  which  accompany  each  form  of  |)oisoniiig  generally 
sufhce  for  diH'erentiation.  in  some  cases,  howe\er,  only  the 
necropsy  and  chemical  analysis  of  the  ingesta  will  hnally 
determine. 


GASTRO-ENTERITIS  123 

G astro-enteritis  may  be  secondary  to  many  disorders  of 
the  stomach  and  bowels,  such  as  cohc,  helminthiasis  (Strongy- 
lus  armatus  inducing  thrombi  and  emboli),  latent  bowel 
ulcers  following  an  attack  of  inliuenza  or  strangles,  and  more 
rarely  mav  be  due  to  enteroliths.  In  the  above-cited  in- 
stances usuallv  the  grave  symptoms  of  severe  inflammation 
are  preceded  bv  milder  symptoms  of  digestive  disorder. 

Course.— The  course  is  usually  rapid,  death  occurring  in 
one  to  three  days.  Some  patients  die  in  a  few  hours  after  the 
symptoms  appear.  In  isolated  cases  the  disease  may  take  a 
subacute  course,  and  end  in  recovery  in  one  to  six  weeks. 
In  the  ox  an  ordinary  gastro-intestinal  catarrh  may  after 
one  to  two  weeks  suddenly  assume  the  form  of  a  gastro- 
enteritis terminating  fatally  in  forty-eight  hours.  Swme  offer 
more  resistance  than  do  horses  or  cattle. 

Prognosis.— Unfavorable  to  bad.  Fully  90  per  cent,  of  the 
patients  attacked  die.  , 

Treatment.— No  food  should  be  given  during  the  attack. 
In  subacute  cases  gruels  (flaxseed  tea)  may  be  allowed.  The 
patient  should  be  kept  dry  and  warm  by  frequent  skin  rubs 
and  warm,  drv  blankets.    Careful  nursing  is  essential. 

The  medicinal  treatment  is  symptomatic  and  of  secondary 
importance.  Mild  laxatives  may  be  used  in  the  early  stages 
(calomel  in  horses  (3j)  and  hogs  (gr.  x),  Glauber  salts  in 
cattle,  castor  oil) .  Strong,  purges  should  be  avoided  (arecalin 
eserin  aloes).  Slimv,  mucilaginous  agents  (linseed  tea,  gum 
arable)  are  indicated.  They  are  usually  used  as  vehicles  for 
opium  (powdered  opium  5ij,  tinct.  opii  5ss-j)  or  belladonna 
(fluidextract  5j)-  Opium  (oij)  combined  with  calomel  (ou), 
and  powdered  althea  (5iij)  in  the  form  of  an  electuary  is 
useful,  ^lorphin  (gr.  iij-v)  may  be  employed  subcutaneously 
to  lessen  pain. 

Gastro-intestinal  disinfectants,  creolin  (5j),  therapogen 
(§ii-iv),  sodium  salicylate  (5i.i-iij)  or  "  sulphocarbolates, 
i  e  sodii  phenolsulphonas  (oij-BJ),  zinci  phenolsulphonas 
(3  j-iv)  are  often  used,  but  are  of  little  value  except  when  the 
bowel  is  still  intact.  They  may  be  even  harmful  m  enteritis. 
In  weakness  and  collapse,  oil  of  camphor  (§j)  subcuta- 
neouslv,  alcohol  (5ij),  ether  (§ij),  caffein  (5ij)  are  indicated. 


124       DISEASES  OF   THE  STOMACH  AND  BOWELS 

Subcutaneous,  intravenous,  or  rectal  injections  of  sterile 
physiological  salt  solution  to  which  2  or  3  per  cent,  of  grape- 
sugar  has  l)een  added  are  reliable.  The  dose  is  II.  c\:  ('. 
Oviij-x.    Calves  and  colts  ()i\',  swine  Oij. 

Croupous  Enteritis  {Monhranoii.s  K)ttrrifis).  Definition. — 
A  subacute  enteritis,  usually  of  cattle,  characterized  patho- 
logically by  the  formation  of  a  fibrinous  pseudomembrane 
o\er  the  mucosa  of  the  intestines. 

Occurrence. — The  disorder  is  not  conmion,  although  iso- 
lated cases  are  noted  in  cattle,  especially  young  fat  bulls  and 
pregnant  cows.  Croupous  enteritis  has  also  been  obser^'ed 
in  horses  and  sheep.  Cattle  which  are  turned  out  to  grass 
very  early  in  the  spring  are  most  often  attacked. 

Etiology. — The  exciting  cause,  which  is  probably  bacterial, 
is  not  known.  Predisposing  causes  are  refrigeration  (cold, 
damp  weather),  irritant  foods  (mustard  grass),  and  the 
ingestion  of  such  drugs  as  strong  camphor  and  canthar- 
ides. 

The  seat  of  the  lesions  is  generally  in  the  small  bowel, 
which  on  necropsy  is  lined  by  a  grayish-yellow,  rather 
friable,  and  easily  removable  mass  under  which  the  mucosa  is 
catarrhally  inflamed. 

Symptoms. — The  early  symptoms  are  those  of  gastro- 
intestinal catarrh  (lost  or  impaired  appetite,  suppressed 
rumination,  constipation,  etc.).  Some  patients  show  colic 
attacks  (switching  of  tail,  kicking  hind  legs  against  abdomen, 
or  more  rarely,  rolling).  The  symptoms  of  colic  temporarily 
recede  in  twelve  to  fourteen  hours.  The  patients  show 
marked  constipation,  which  usually  last  one  or  two  weeks, 
at  the  end  of  which  time  the  symptoms  of  abdominal  i)ain 
return  and  diarrhea  sets  in.  "^riie  li(iui(l  feces  are  brown  in 
color,  quite  fetid,  and  eventually  admixed  with  yellowish- 
gray  croupous  masses  in  the  form  of  shreds,  flakes,  or  some- 
times cylinders  several  feet  in  length.  These  tubular  masses 
ap])ear  to  the  novice  as  portions  of  the  intestines  from  which 
they  are  differentiated  by  their  homogeneous  structure, 
absence  of  mesentery,  and  bloodvessels.  The  cylinders  often 
contain  feces. 

In  some  mild  cases  the  passage  of  croupous  masses  is  not 


G  ASTRO-ENTERITIS  125 

preceded  by  symptoms  of  ill  health  beyond  those  of  a  mild 
indifijestion.  In  other  cases  the  prodromal  symptoms  are 
those  of  a  severe  gastro-enteritis,  with  great  prostration,  lost 
appetite,  high  fever,  bowel  hemorrhage,  etc. 

Diagnosis. — A  diagnosis  is  only  possible  when  croupous 
meml)ranes  are  found  mixed  with  the  feces.  Shreds  of  the 
pseudomembranes  may  be  mistaken  for  worms,  prolapsed 
bowel,  and  portions  of  tendons  accidentally  swallowed. 

Course. — The  course  is  usually  one  or  two  weeks,  ending  in 
recovery.  Death  occurs  only  in  those  cases  in  which  symp- 
toms of  severe  gastro-enteritis  appear  or  more  rarely  may  be 
due  to  a  complete  obstruction  of  the  bowel  through  the 
accumulation  of  fibrinous  masses. 

Prognosis. — Usually  good.    Most  cases  recover. 

Treatment. — A  large  dose  of  salts  (lbs.  j-ij)  is  very  useful. 
It  may  be  followed  by  the  administration  of  oils  (raw  linseed 
or  castor  oil  Oj-ij).  The  after-treatment  is  the  same  as 
recommended  in  gastro-intestinal  catarrh  (diet,  hygiene, 
stimulants,  demulcents) . 

Mycotic  Gastro-enteritis  [S  ilnge  Poisouing.  Forage  Poison  - 
ing.  Mold  Poisoning.  Cry ptogamic  Poisoning.  Falsely  railed 
"  Cerebrospinal  Meningitis."  Leuko-encephalitis) .^Definition. 
— A  form  of  gastro-enterosis  leading  to  intoxication  of  the 
central  nervous  system,  affecting  herbivorous  animals  and 
due  to  the  ingestion  of  food  infested  with  certain  moulds. 
The  disorder  is  probably  not  a  clinical  entity. 

Occurrence. — Forage  poisoning  is  very  prevalent  in  the 
Ignited  States,  appearing  particularly  among  horses  which 
have  eaten  corn  silage,  shredded  fodder,  corn  stalks  or  corn 
cobs.  The  disorder  may,  however,  occur  in  horses  on  pasture 
and  which  have  not  been  fed  corn.  During  hot,  showery 
seasons  the  rank  growth  of  grass,  which  mats  together,  forms 
an  ideal  medium  for  the  development  of  various  moulds 
which  are  pathogenic.  In  all  probability  water  drunk  from 
stagnent  pools  or  shallow  wells  may  also  be  a  factor.  Lands 
in  low  flat  sections  which  are  periodically  flooded  by  streams 
flowing  through  them  are  especially  dangerous  in  this  regard. 
The  disease  is  therefore  quite  prevalent  along  the  river 
valleys  of  the  United  States.     Cattle  and  sheep  are  also 


12(')       DISEASES  OF   THE  STOMACH   AM)  BOWELS 

affected,  but  less  frequently  than  are  horses.  Cattle  are  some- 
times infected  while  on  orchard  pastures,  the  ground  strewn 
with  "wind-fall"  apples,  which  they  eat.     (Acidosis?) 

Etiology. — Moulds  (mucor,  aspergillus,  penicillium), 
"blights"  or  smuts  (Tilletia  caries,  ustilago),  rusts  (puccinia, 
uromyces),  and  yeasts  (Polydesmus  exitiosus),  which  infest 
forage,  grain,  and  water  at  times,  are  pathogenic,  and  through 
their  toxins  produce  in  the  animal  body  symptoms  which  fall, 
generally  speaking,  under  two  groups,  viz.,  gastro-intcstinal 
and  nervous.  In  some  outbreaks  the  nervous  symj)toms  pre- 
dominate, in  others  the  gastro-intestinal,  depending  i)robably 
on  the  kind  of  fungus  taken  into  the  body,  the  (piantity  of 
toxins  produced,  and  the  resistance  of  the  individual. 

Symptoms. — The  symptoms  of  forage  jjoisoning,  as  noted, 
may  be  grouped  under  two  heads.  (1)  nervous,  and  (2) 
gastro-intestinal.  Either  may  dominate  or  both  may  be 
combined  in  individual  outbreaks. 

Nervoii.s'  (houp. — The  most  conspicuous  sym])toms  are 
dysphagia  from  paralysis  of  the  pharynx  (inability  to  swallow, 
slobbering),  paralysis  of  tongue,  roaring,  incoordination  of 
body  movements,  staggering,  shambling  gait,  weakness  of 
hind  parts;  strikes  fore  feet  in  stepi)ing  over  door  sill,  paraly- 
sis of  tail),  spasms  of  certain  gr()Uj)s  of  muscles  (twitching  of 
face,  lips,  neck,  shoulder) ;  mental  excitement,  due  to  active 
cerebral  congestion,  causing  rabiform  symptoms  (tendency  to 
climb  over  any  obstacles,  biting  and  striking  at  attendants), 
mental  (ie])ression  (stui)()r,  j)ushing  head  against  wall) ;  forced 
mo\'ements  (traveling  in  a  circle  to  right  or  left,  individual 
patients  always  in  one  direction);  amaurotic  blindness  (run- 
ning against  objects),  opisthotonos  (head  drawn  backward), 
and  finally  profuse  diaphoresis  (heavy  sweats  along  neck, 
shoulders,  sometimes  on  one  side  only,  may  lead  to  loss  of 
hair  from  maceration). 

(jla.ffro-intestinal  Symptoms. — Colic  (pawing,  restlessness), 
constipation,  often  obstinate  at  first,  or  diarrhea,  the  feces 
liquid,  sometimes  blood-stained  and  fetid.  There  is  occa- 
sionally slight  bloating.  The  jieristalsis  is  suppressed  in 
constipation,  lively  in  diarrhea.  Tenesmus  is  occasionally 
observed. 


G  ASTRO-ENTERITIS  127 

General. — The  conjunctiva  shows  petechia  and  icterus,  the 
temperature  in  the  early  stages  is  up  to  105°  F.,  but  soon 
drops  to  normal  or  subnormal,  where  it  continues  until  death. 
The  pulse  is  usually  normal  until  the  last  stages,  when  it 
becomes  rapid  (occasionally  slower),  weak,  and  irregular. 
Dyspnea  is  generally  present,  but  varies  greatly  in  degree  in 
different  cases.  Occasionally  the  respirations  are  subnormal. 
Polyuria  is  noted  in  some  outbreaks,  although  retention  of 
urine  (paralysis  of  bladder)  is  more  commonly  observed. 
In  the  ox  hematuria  is  often  a  symptom.  Stomatitis  and 
eczemas  of  skin  (especially  of  head)  have  been  noted  in  some 
outbreaks. 

Diagnosis. — Usually  the  diagnosis  is  not  difficult.  The 
number  of  animals  affected,  the  history  of  food  eaten  (silage, 
shredded  fodder),  the  nervous  symptoms,  rapid  course,  and 
the  lack  of  apparent  contagiousness  are  important  factors. 
The  disease  might  be  confused  with  rabies,  hemorrhagic 
septicemia,  anthrax,  and  poisoning  with  drugs.  In  most 
outbreaks  a  combination  of  nervous  and  gastro-intestinal 
symptoms  is  suggestive.  Differentiation  in  sporadic  cases 
may  be  impossible  without  the  aid  of  a  necropsy  and  bacte- 
riological examination  (rabies,  anthrax,  hemorrhagic  septi- 
cemia ) . 

Course. — The  course  is  usually  rapid.  Individual  patients 
die  apoplectic,  others  in  a  few  hours  (seven  to  twelve),  while 
many  live  one  or  two  weeks  and  succumb.  Patients  which 
recover  usually  do  so  gradually,  and  such  sequelae  as  lumbar 
weakness  (wobbling  gait),  hemiplegia  (paralysis  with  atrophy 
of  the  muscles  of  one  side  of  the  body),  blindness,  epilepti- 
form seizures,  etc.,  follow  and  persist  for  weeks  or  months. 
In  occasional  cases  relapses  occur  during  convalescence. 

Prognosis. — The  prognosis  is  doubtful  to  bad.  The  mor- 
tality varies  from  25  to  90  per  cent. 

Treatment. — Feeding  infested  forage  or  water  should  be 
immediately  stopped.  Pastured  animals  should  be  placed  in 
stables  and  fed  only  uncontaminated  foods.  ^Yhile  the  separa- 
tion of  the  healthy  from  the  sick  does  not  seem  necessary, 
as  an  extra  precaution  it  is  recommended  at  least  until  our 
knowledge  of  the  etiology  is  more  definite. 


128       DISEASES  OF  THE  STOMACH  AND  BOWELS 

Medicinal. — The  patients  should  be  purged  as  soon  as 
possible  (aloin  5j-ij;  salts,  lbs.  j-ij;  arecalin,  gr.  j-ij,  com- 
bined with  strychnin  gr.  |).  Large  doses  are  usually 
required  to  move  the  bowels.  Calomel  (5  j-ij)  is  useful  in 
horses.  Owing  to  pharyngeal  paralysis  drenching  is  contra- 
indicated.  ^Medicine  should  be  given  j^f'r  orrm  in  form  of  boli 
or  electuaries. 

The  purgative  may  be  followed  by  a  disinfectant,  such  as 
Pearson's  creolin  (5j-ij)>  therapogen  (oij~iv),  etc.  In  weak- 
ness and  collapse  give  alcohol  (5ij),  ether  C^ij).  caffcin  (oij), 
oil  of  cami)h()r  (,^j)  sul)Cutaneously.  For  remainder  of 
treatment  see  Simi)le  (iastro-entcritis  and  Pharyngitis. 

When  patient  begins  to  im])rovc  and  eat  it  should  be  placed 
on  a  light  laxative  diet.  If  able  to  stand  in  them,  support 
with  slings. 

Toxic  Gastro-enteritis. — Toxic  gastro-enteritis  is  an  inflam- 
mation of  the  stomach  and  bowels  due  to  the  ingestion  of 
poisons  such  as  arsenic,  mercury  or  any  irritant  drug  or  chem- 
ical. The  symptoms  and  treatment  of  this  form  of  gastro- 
enteritis are  best  given  in  books  on  toxicology  which  deal  with 
poisons,  their  afl'ccts  and  antidotes. 

TRAUMATIC  INDIGESTION  OF  THE  OX. 

Traumatic  Gastritis. 

Definition. — An  inflammation  of  the  stomach  (rumen  or 
reticulum)  due  to  foreign  bodies  ingested  with  the  food. 

Occurrence.  The  disorder  is  coiiimon  in  cattle,  especially 
dairy  cows  the  pr()])erty  of  the  poorer,  shiftless  dairymen  who 
permit  nails,  wire,  needles,  bolts,  etc.,  to  accumulate  in  the 
feed  troughs  or  where  the  cattle  feed.  Cows  with  woman 
attendants  frequently  swallow  darning  needles,  hair-pins, 
open  safety-])ins,  etc.,  which  come  from  the  clothing  and  hair. 
On  farms  where  the  hay  is  baled  for  market,  pieces  of  baling 
wire  are  commonly  picked  up  by  the  cattle.  Where  the 
herd  is  grazing  on  flooded  pastures  or  must  drink  from  shallow 
sandy  springs  large  quantities  of  silt  and  sand  will  be  ingested. 

Cattle  which  have  developed  the  habit  of  licking^stable 
walls,   partitions,   etc.,   which   may   develop^intothe   vicg 


TRAUMATIC  INDIGESTION  OF   THE  OX  129 

known  as  "  pica,"  take  into  the  stomach  considerable  deleteri- 
ous foreign  matter. 

Sometimes  masses  of  hair  (wool  in  sheep)  are  hcked  off  other 
animals,  or  usually  due  to  some  itching  skin  lesion,  from  the 
patient  itself.  These  accumulations  form  hair  (or  wool) 
balls  in  the  stomach. 

Etiology. — The  fact  that  an  animal  ruminates  does  away 
with  the  necessity  of  thorough  mastication  following  pre- 
hension. The  food  is  rolled  in  the  mouth  by  the  tongue, 
which  is  not  very  sensitive,  mixed  with  saliva  and  swallowed 
without  being  chewed.  Any  foreign  bodies  in  it,  therefore, 
usually  reach  the  stomach.  While  blunt  foreign  bodies  usually 
do  no  harm  unless  large  quantities  of  them  accumulate,  or  if 
they  block  the  natural  openings  of  the  stomach,  sharp- 
pointed  objects  (needles,  wire,  nails)  are  frequently  forced 
through  the  walls  of  the  reticulum  by  the  peristaltic  move- 
ments, causing  a  traumatic  gastritis.  Usually  the  sharp- 
pointed  object  penetrates  the  diaphragm  in  the  direction  of 
the  heart  sac.  Sometimes  another  route  is  taken,  the  wire, 
needle,  etc.,  entering  the  lung,  liver,  spleen,  uterus,  or  even 
aorta,  where  it  sets  up  a  suppurative  inflammation  leading  to 
abscess  formation  or  fatal  hemorrhage.  In  some  cases  the 
abscesses  may  become  encapsuled  and  the  condition  latent, 
or  by  way  of  metastasis,  pyemia  with  multiple  abscess  for- 
mation in  parenchymatous  organs  (lungs,  liver)  results. 

Symptoms.- — In  general  the  symptoms  are  those  of  an 
indigestion  not  traceable  to  erroi^  in  diet,  which  is  period- 
ical (remissions  and  exacerbations),  and  often  associated  with 
rheumatic-like  stiffness  of  the  patient.  Blunt  foreign  bodies 
produce  symptoms  of  indigestion,  which  without  a  clear 
history  of  the  case  are  extremely  difficult  to  differentiate 
from  chronic  gastric  catarrh.  Accumulations  of  sand  or  silt 
in  the  rumen  sometimes  induce  symptoms  of  loss  of  appetite, 
suppressed  rumination,  slobbering,  stiffness  of  movement, 
and  frequent  groaning.  In  some  cases  the  rumen  feels  ab- 
normally hard  on  palpation  and  the  feces  will  be  found  to 
contain  particles  of  sand.  Occasionally  the  cattle  will  show 
toxic  symptoms  resembling  those  of  parturient  paresis. 

If  the  blunt  foreign  bodies  block  the  natural  openings  of 
9 


inO       DISEASES  OF  THE  STOMACH  AND  BOWELS 

the  stomach  sudden  illness  is  produced.  This  is  most  com- 
monly seen  in  calves  and  lambs  where  hair,  wool,  or  food 
balls  are  the  ofVending  objects.  The  symptoms  are  those  of 
bloatinj;,  colic,  restlessness,  retching,  dyspnea  and  occasion- 
ally epileptiform  attacks. 

Shari)-])ointe(l  foreign  bodies  produce  symptoms  of  sub- 
acute gastro-enteritis,  which  is  intermittent  in  course.  The 
patient  shows  usually  symptoms  of  indigestion,  bloating, 
stiffness  and  falls  off'  in  flesh.  Pinching  the  patient  in  the 
centre  of  the  back,  percussion  o\'er  the  region  of  the  attach- 
ment of  the  diaphragm,  and  palj)ati()n  over  the  region  of 
the  reticulum  produce  pain.  The  gait  of  the  animal  is  stiff, 
dyspnea  appears  on  exercise,  the  temperature  is  somewhat 
elevated,  and  the  patient  usually  considerably  prostrated. 
Parturition,  railway  journeys,  and  placing  the  hind  end  of  the 
animal  higher  than  the  front  cause  the  sym])t()ms  to  become 
worse.  The  usual  treatment  for  indigestion  is  ineffective. 
As  a  rule,  in  time  symptoms  of  traumatic  pericarditis  develoj) 
(see  this). 

Diagnosis. — The  diagnosis  depends  largely  ui)()n  the  history 
of  the  case  (no  dietetic  errors),  the  intermittent  and  variable 
character  of  the  symptoms,  the  stiffness  of  the  patient,  and 
the  result  of  percussion  and  palpation  over  the  region  of  the 
diaphragm  and  reticulum.  It  has  been  suggested  that  drugs 
which  stimulate  gastric  movements  be  used  to  aid  in  diag- 
nosis. For  instance,  1-to  2-grain  doses  of  arecalin  or  1-grain 
doses  of  sulphate  of  veratrin  given  subcutaneously  will  cause 
in  cases  of  traumatic  indigestion  contractions  of  the  stomach 
with  which  are  associated  great  restlessness,  groaning,  and  a 
general  intensification  of  the  symptoms,  the  condition  of  the 
animal  becoming  worse.  In  ordinary  indigestion,  on  the 
other  hand,  the  administration  of  such  drugs  will  tend  to 
improve  the  condition  of  the  patient.  There  are,  howe\'er,  a 
great  many  exceptions  to  this  rule.  In  some  cases  a  diagnosis 
can  only  be  made  on  necropsy. 

Traumatic  indigestion  may  be  confused  with  chronic 
gastro-intestinal  catarrh,  bloating,  tuberculosis  of  the  medi- 
astinal lym])h  glands,  ])neumonia,  or  j^leuritis.  Tlu>  differen- 
tiation is  aided  by  the  history  of  the  case,  the  sj)ecific  symp- 


TRAUMATIC  IX DIGESTION  OF   THE    OX  131 

toms  of  traumatic  indigestion  (stiffness,  intermittency),  and 
in  tuberculosis  through  the  tubercuhn  test. 

Course. — The  course  of  the  disorder  produced  l\v  foreign 
bodies  is  generally  chronic,  lasting  for  weeks  or  months. 
Occasionally,  due  to  the  fact  that  a  blunt  foreign  body  ob- 
structs a  natural  opening  or  a  sharp  one  begins  to  wander  in 
the  body,  symptoms  such  as  described  are  suddenly  precipi- 
tated, which  result  in  death  in  a  short  time;  thus  accumula- 
tions of  sand  in  the  rumen  may  cause  death  in  two  or  three 
weeks,  obstructing  hair  or  wool  balls  in  one  or  two  days.  In 
some  instances  the  condition  may  heal  spontaneously  if  the 
sharp  foreign  body  works  back  into  the  stomach  or  in  case  it 
perforates  the  wall  of  the  abdomen,  producing  an  abscess 
and  subsequently  a  fistula,  through  which  it  makes  its  escape 
into  the  outside  world.  These  terminations,  however,  are 
comparatively  rare.  In  practice  most  of  the  patients  which 
develop  clinical  symptoms  either  die  of  traumatic  heart  dis- 
ease or  pyemia. 

Prognosis. — The  prognosis  is  usually  bad.  ]\Iost  cases  die 
with  pyemia  or  heart  disease. 

Treatment. — ^Medicinal  treatment  is  of  little  value,  although 
until  a  diagnosis  is  established  it  is  recommended  to  treat  as 
in  gastro-intestinal  catarrh.  In  a  few  instances  surgical  inter- 
ference has  been  successful.  Rumenotomy  may  be  per- 
formed and  the  foreign  body  removed,  pro%ided,  of  course, 
it  has  not  completely  penetrated  the  wall  of  the  reticulum. 
Another  method  is  to  cast  and  place  the  patient  on  its  back. 
The  operator  stands  with  one  foot  on  a  chair  and  the  other 
on  the  body  of  the  patient  over  the  region  of  the  ensiform 
cartilage.  By  pressing  the  abdominal  wall  in  this  region 
downward  with  his  foot  seven  to  ten  times  it  is  claimed  the 
foreign  body  will  be  made  to  slip  back  into  the  reticulum. 
However,  it  would  be  just  as  liable  to  penetrate  in  some  other 
direction,  injuring  new  organs.  Its  use  is  therefore  not 
unattended  with  danger. 

As  a  general  proposition  the  immediate  slaughter  of  the 
patient  is  recommended.  From  a  prophylactic  standpoint, 
removing  foreign  bodies  from  the  mangers,  keeping  cattle 
away  from  where  hay  has  been  baled,  etc.,  are  important. 


CHAPTER   IV. 

ANIMAL  PARASITES  IX  THE  STOMACH. 
HELMIXTIHASIS. 

GASTROPHILUS.      BOTS. 

Varieties.  -The  larvjv  of  l)()t  flies  occur  in  the  stomach 
and  l)o\vel  of  the  horse.  The  folh)\vino:  varieties  have  been 
described:  (a)  (lastrophihis  eqiii,  which  is  usually  found 
in  the  esophageal  ])ortion  of  the  stomach.  (6)  Gastropliilus 
pecorum,  found  in  the  "stomach,  duodenum  and  rectum 
(Hungarian  and  Russian  horses),  (r)  Gastrophilus  henior- 
rhoidalis,  found  in  the  pyloric  ])()rtion  of  the  stomach, 
duodenum,  and  rectum,  (r/)  Gastro])hilus  nasalis,  found 
in  the  pyloric  portion  of  the  stomach  and  duodenum. 

Life  History. — The  female  botfly,  which  is  common  in 
summer,  flying  over  the  pasture  fields  and  roads,  deposits 
her  eggs  on  the  skin  of  the  horse,  especially  on  the  hairs  of 
the  front  legs,  mane,  neck,  and  about  the  nose  and  mouth. 
In  from  three  to  five  days  there  issue  from  the  eggs  the 
larvae,  which  are  licked  oft"  by  the  horse,  reach  the  stomach, 
where  they  attach  themselves  to  the  mucous  membrane,  to 
remain  until  the  following  spring.  In  the  months  of  May 
to  July,  and  sometimes  during  the  late  summer,  the  bots 
leave  the  stomach,  pass  into  the  intestines  and  are  voided 
with  the  feces.  Either  on  the  ground  or  in  the  mainu'c  they 
change  into  the  chrysalis  stage.  In  about  one  month  the 
mature  fly  emerges,  and  after  coi)ulati()n  the  females  deposit 
their  eggs  as  described. 

The  gastrus  larva'  are  found  in  the  stomach  of  all  horses 
on  pasture  in  small  towns  or  wiiere  the  botfly  api)ears. 
Generally  speaking,  the  larvte  are  harmless.  Only  in  very 
exceptional  cases  do  they  cause  illness  through  traumatic 
gastritis  (symptoms  of  indigestion,  intermittent  attacks  of 


ANIMAL  PARASITES  IN  THE  INTESTINES        133 

colic  and  emaciation,  especially  in  colts).  In  still  rarer 
instances  they  produce  perforation  of  the  stomach  and 
peritonitis.  Once  in  a  while  bots  induce  inflammation  of  the 
rectum  or  even  prolapsus  recti,  and  still  more  rarely  they  may 
enter  the  brain,  larynx,  and  other  organs. 

Treatment. — The  only  agent  of  any  \alue  to  eliminate 
the  bot  larvaj  is  the  disulphid  of  carbon.  It  should  be 
administered  on  an  empty  stomach  in  capsules  in  doses  of 
Siiss,  four  doses  of  which  are  given,  with  an  hour  between 
each.  After  twelve  to  twenty  hours  administer  a  good 
purgative. 

Prophylaxis. — Prevention  consists  in  destroying  the  bot 
flies  when  observed  about  horses  and  by  removing  the  eggs 
from  the  hairs  once  a  week  with  a  sharp  knife.  Cleaning 
out  of  the  underbrush  in  woods,  pastures,  along  the  road- 
ways, and  in  the  fields  is  contributory  to  this  elimination. 

SPIROPTERA. 

These  nematodes  appear  in  the  stomach  of  the  horse  and 
ass,  where  they  form  tumors  in  the  pyloric  portion,  varying 
in  size  from  a  hickory  nut  to  a  hen's  egg.  When  a  tumor  is 
incised  the  thin,  thread-like  worm  appears.  They  sometimes 
induce  gastritis  and  colic. 

Spiroptera  strongylina  occurs  in  the  stomach  of  swine 
and  sometimes  induces  an  enzootic  gastritis. 

ANIMAL  PARASITES  IN  THE  INTESTINES. 

Tapeworms  (Cestodes). — Life  Cycle. — In  its  development 
the  tapeworm  passes  through  two  stages,  viz.:  the  cyst  or 
larval  form  and  the  adult  tapeworm.  Usually  the  cyst 
is  found  in  one  animal  host  and  the  tapeworm  in  another. 
The  hosts  are  usually  not  even  of  the  same  species.  As  an 
example,  the  tapeworm  Taenia  coenurus  has  for  its  host  the 
dog,  while  the  larval  stage,  the  Coenurus  cerebralis,  has  for 
its  host  usually  the  sheep.  The  Taenia  cucumerina,  the 
common  tapeworm  of  the  dog  in  its  cyst  form,  is  harbored 
by  the  common  dog  flea  (Pulex  serraticeps). 


134  ANIMAL  PARASITES   IX   THE  STOMACH 

The  development  of  the  tapeworm  is  as  follows:  The  eggs 
with  the  segments  of  the  adult  worm  which  inhabits  the 
intestines  are  voided  with  the  feces  and  thus  reach  the  out- 
side world.  There  they  are  taken  up  by  a  second  host,  in 
the  stomach  of  which  the  embryo,  often  provided  with  hooks, 
is  hatched.  These  embryos  penetrate  the  bowel  wall  and 
inter  the  bloodvessels,  and  are  carried  to  distant  organs, 
such  as  the  muscles,  brain,  lungs,  etc.,  developing  in  these 
organs  cysts.  If  organs  containing  such  cysts  are  ingested 
by  animals  which  would  form  the  proper  host  there  develops 
in  the  intestine  a  tapeworm.  Tlie  tapeworm  is  provided  with 
a  head  or  scolex  to  which  is  attached  a  number  of  segments 
or  colonies  that,  when  ri])e,  contain  the  fertile  egg  of  the 
tapeworm. 

Varieties. — Each  of  the  domesticated  animals  has  species 
of  tapeworms  peculiar  to  itself. 
Ilurse:  1.  Taenia  perfoliata. 

2.  Tjenia  plicata. 

3.  Taenia  mamillana. 
Ox:  1.  Taenia  expansa. 

2.  Taenia  denticulata. 

3.  Taenia  alba. 
Sheep:  1.  Taenia  expansa. 

2.  Taenia  ovilla. 

3.  Taenia  alba. 

4.  Taenia  fimbriata. 

Symptoms. — Tapeworms,  unless  ])resent  in  large  number, 
rarely  produce  sym-ptoms.  For  instance,  over  50  per  cent, 
of  the  dogs  harbor  tapeworms,  particularly  the  Taenia  cucum- 
erina.  On  the  other  hand,  ta])eworms  sometimes  cause 
chronic  intestinal  catarrh  (diarrhea  alternating  with  con- 
stipation, icterus,  and  eventually  anemia).  In  horses  colic 
may  be  caused  by  them.  In  sheep  they  induce  chronic 
bowel  catarrh,  anemia,  and  often  fatal  cachexia.  In  rare 
instances  a  ])erforative  ])eritonitis  may  be  due  to  tai)eworms. 

Diagnosis. — Tteniasis  can  l)e  diagnosed  ])ositively  only  by  an 
examination  of  the  feces  in  which  will  be  found  the  segments 
or  eggs  of  the  tapeworm.  In  sheep  a  diagnosis  may  be  made 
by  a  nccroi)sy. 


AXIMAL  PARASITES  IX  THE  IXTESTIXES         135 

Treatment.— In  horses  the  most  valuable  tapeworm  agent 
is  tartar  emetic  (5ss)  daUy  for  three  or  four  days.  Turpen- 
tine (oj-ij)  is  a  good  t^niafuge.     It  should  be  given  m  milk 

or  oil  to  prevent  blistering  the  mouth  or  throat.  

In  lambs  picrate  of  potash  (gr.  ij-vj),  kooso  (gr.  ij-iij) 
or  male  fern  (5j)  are  recommended.  Tteniafuges  should 
be  given  on  an  empty  stomach  and  followed  in  twelve  to 
twenty  hours  by  a  good  purge.  Treatment  is  successful  only 
when  the  head  of  the  tapeworm  is  also  removed. 

Prevention.— In  dealing  with  an  enzootic  of  ta^niasis  it  is 
advisable  to  give  the  animals  plenty  of  good,  nutritive 
food  and  excellent  care.  Sometimes  these  alone  are  all  that 
is  necessary.  Obviously,  cysts  and  tapeworms  should  be 
destroved  as  a  preventive  measure. 

Round-worms    {Asca  rides). —The     ascarides     or     round- 
worms resemble  earthworms  somewhat  in  form.    The  life- 
cvcle  of  these  parasites  has  not  yet  been  fully  deternimed. 
Unlike  the  tapeworms,  they  do  not  seem  to  require  an  inter- 
mediate   host.      The    transmission   to    susceptible    animals 
occiu-s  through  the  ingestion  of  fecal  matter  containing  the 
eggs  and  not  through  drinking  water.     :Milk,  however,  can 
become  contaminated   and   therefore   very   young  animals 
are  infested.    The  development  of  the  embryo  from  the  egg 
is  verv  rapid.    For  instance,  the  egg  of  the  Ascaris  megalo- 
cephala  of  the  horse  will  develop  a  complete  emb\TO  in  three 
days.    The  following  are  the  varieties  of  ascarides: 
Horse:  Ascaris  megalocephala. 
Ox  and  Swine:  Ascaris  lumbricoides. 
Symptoms.— In    most    cases    round-worms    produce    no 
svmptoms.    Occasionally,  however,  if  large  numbers  of  them 
are  present  in  the  intestine  they  will  produce  symptoms  ot 
chronic  intestinal  catarrh,  obstruction  of  the  bowel  or  more 
rarelv  hemorrhagic  enteritis.     A  few  exceptional  cases  ot 
bowel  perforation  with  fatal  peritonitis  have  been  due  to 
round-worms.    At  times  they  may  block  up  the  bile  ducts 
and  produce  icterus.     Besides  acting  in  a  mechanical  way  it  is 
verv  possible  that  round-worms  eliminate  a  toxic  substance 
which  acts  upon  the  nervous  system,  producing  symptoms  of 
epilepsv.  tetanus  or  paralysis  (anaphylaxis?).     In  calves  an 


13G  .4A7.U.IL   I'AHASITFS   f\   THE  ^rOMACIl 

enzootic  ascariasis  has  been  oljserved  leading;  to  considerable 
losses  from  synii)t()nis  of  chronic  intestinal  catarrh  (diarrhea). 
Peculiar  to  these  cases  is  a  penetratinji;  ether-like  odor  of  the 
breath  of  the  sick  ])atient.     The  meat  has  also  a  similar  smell. 

Treatment. — In  the  horse  tartar  emetic  (§ss)  may  be  given 
or  Fowler's  solution  of  arsenic  (5j),  <>i'  arsenic  (gr.  xv- 
xxx).  Turpentine  (5ij)  i'l  <>il  (^)j)>  Jmd  bisul])hid  of  carbon 
(5ij  in  oil  Oj)  are  also  recommended. 

Calves  may  be  given  tartar  emetic  (gr.  xlv)  dissolved  in 
water  (Bv),  one  tablespoonful  every  three  hours  in  milk. 
For  swine areca  nut  (5 j^i'^')  ^^ith  Hour  as  an  electuary  is  good. 

Prophylaxis. — To  prevent  reinfection  it  is  recommended 
to  burn  the  manure  of  the  affected  and  thoroughly  disinfect 
the  stable. 

Palisade-worms  in  the  Intestine. — Following  are  impor- 
tant worms  of  this  group: 

Horse:  Strongylus   armatus   and   tetracanthus. 
Sheep:  Strongylus  eontortus. 
O.y:  Strongylus  convolutus. 

Strongylus  Armatus  {Sclerostonium  Equinum). — Strongylus 
armatus  is  the  most  common  of  the  palisade-worms  of  the 
horse.  Its  life-cycle  is  not  entirely  understood.  Three 
varieties  have  been  described :  (a)  Sclerostomum  bidentatum, 
(6)  Sclerostomum  edentatum  and  (c)  Sclerostomum  cpiad- 
ridentatum. 

Sclerostomum  Bidentatum. — Sclerostomum  biden- 
tatum is  the  cause  of  the  common  worm  aneurysm  found  in 
90  per  cent,  of  all  horses  in  the  trunk  of  the  anterior  mesen- 
teric artery.  The  mature  worm  lives  in  the  large  intestine 
of  the  horse.  The  eggs  are  voided  with  the  feces  where  they 
hatch,  producing  the  larval  form.  The  larvae  are  taken  up 
with  contaminated  food  and  bedding  by  healthy  horses 
and  reach  the  intestines.  From  the  lumen  of  the  intestines 
they  pass  probably  into  the  veins  of  the  mucous  membrane 
and  reach  the  li\er  through  the  i)ortal  circulation;  or  they 
may  pass  into  the  lungs  through  the  right  heart  and  from 
the  lungs  enter  the  general  arterial  circulation.  In  the 
trunk  of  the  anterior  mesenteric  artery  they  form  the  worm 
ancur\sm  which  is  one  of  tlie  causes  of  colic  (embolic)  in  the 


ANIMAL  PARASITES  IN  THE  INTESTINES        137 

horse.  The  emigration  of  the  hirvtie  from  the  aneurysm 
back  to  the  intestine  occurs  in  that  they  are  carried  by  the 
arterial  blood  to  the  peripheral  intestinal  arteries.  They 
then  form  embolic  worm  nodules  in  the  bowel  walls.  Later 
the  larva^  perforate  the  nuicous  membrane,  reenter  the 
bowel  and  attain  sexual  maturity. 

ScLEROSTOMUM  EIdentatum. — Tliis  parasite  is  found 
in  the  large  intestine  in  about  one-half  of  the  horses.  The 
eggs  are  passed  out  with  the  feces.  The  embryos  are  taken 
up  with  the  food  and  water  and  enter  the  digestive  tract 
of  healthy  horses.  They  pass  into  the  bowel  walls  and  reach 
the  subserosa  of  the  parietal  peritoneum,  where  they  produce 
hemorrhages  in  the  peritoneum.  Occasionally  in  colts  they 
cause  anemia.  Their  presence  frequently  induces  an  ad- 
hesive peritonitis.  Rarely  the  parasite  is  found  free  in  the 
abdominal  cavity  or  in  the  scrotum.  From  the  subserosa 
the  larvse  wander  between  the  leaves  of  the  mesentery  back 
to  the  large  intestines,  in  the  wall  of  which  they  become 
encysted.  They  later  enter  the  lumen  of  the  bowel  and  attain 
sexual  maturity. 

ScLEROSTOMUM  QuADRiDENTATUM. — Sclcrostomum  quadri- 
dentatum  is  very  rare  and  does  not  seem  to  have  a  pathogenic 
action. 

Strong  !fLUS  Tetracanthus. — This  palisade- worm  lives 
in  the  mature  state  in  the  colon  where  often  large  numbers 
appear  in  colts.  They  produce  a  hemorrhage  and  even 
necrotic  enteritis  with  colic  and  bloody  diarrhea.  In  the 
feces  large  numbers  of  very  small  strongyli  are  found. 
Sometimes  death  results  from  bowel  hemorrhage.  The 
eggs  pass  out  with  the  feces  and  from  them  rod-shaped 
embryos  form  which  are  ingested  by  horses  with  the  food. 
In  the  intestines  they  bore  into  the  mucous  membrane  of  the 
colon  and  cecum  and  become  encysted.  There  are  frequently 
found  as  submucous  nodules  in  the  middle  of  which  are  the 
larvae  surrounded  by  pus.  Finally  the  larvae  penetrate  the 
capsule  into  the  lumen  of  the  bowel  where  they  reach  sexual 
maturity. 

Treatment. — The  treatment  consists  in  the  use  of  vermi- 
fuges as  recommended  for  round-worms.     Of   late   atoxyl 


138  ANIMAL  PARASITES   IN   THE  STOMACH 

(gr.  v)  given  in  repeated  doses  once  daily  lias  been  recom- 
mended for  colts. 

Prcirnfion. — As  a  i)reventive  measure  filtering  the  drinking 
water  is  advisable. 

Strongylus  Contortus. — This  is  commonly  known  as  the 
twisted  i)alisade-worm,  and  is  the  cause  of  the  so-called 
stomach-worm  plague  of  the  sheep.  The  life-cycle  of  this 
parasite  is  not  understood.  Probably  the  embryos  are  taken 
uj)  on  the  pastures  or  j)erhai)s  in  the  sheepfold.  The  stomach- 
worm  plague  which  this  parasite  induces  is  a  serious  disease 
of  lambs  in  the  spring  or  during  wet  summers.  The  condition 
may  become  enzootic,  causing  great  economic  losses. 

Si/iiiptom6-. — The  symptoms  in  general  are  those  of  a 
chronic  gastro-intestinal  catarrh  leading  to  emaciation, 
anemia,  hydremia,  and  death.  On  postmortem  the 
abomasum  of  the  infested  sheep  will  be  found  to  contain  a 
large  number  of  the  small,  hliform,  reddish  parasites,  2  or  3 
cm.  in  length.  As  noted,  picrate  of  potash  (gr.  ij-viij)  is 
recommended. 

Strongylus  Convolutus. — This  ])arasite  is  found  in  young 
cattle  and  calves,  also  in  sheep.  It  occurs  in  the  abomasum, 
where,  under  the  epithelial  layer  of  the  mucous  membrane, 
it  forms  gray,  pin-head  to  pea-sized  nodules  which  contain 
the  parasites.  If  present  in  large  numbers  they  produce 
symptoms  of  gastric  disturbance  leading  to  diarrhea,  emacia- 
tion, and  cachectic  hydremia. 

CEsophagostoma  in  the  Intestines  {Nudule  Disease). — The 
larvae  of  the  oesophagostomum  frequently  produce  disease, 
especially  among  cattle  and  sheep.  Inasmuch  as  the  mo.st 
characteristic  lesion  on  necrojisy  is  the  nodule  ])r()duced  by 
the  larvie,  the  name  "nodule  disease"  has  been  given  to  this 
disorder.  The  following  a'sophagostomas  occur  in  domesti- 
cated animals: 

(tt)  (Esophagostomum  columbianum  of  the  intestines 
(.\merican  sheep). 

(h)  (Ksophagostomum  radiatuni  in  the  intestines. 

{<•)  (Ksophagostomum  venulosum  of  Euroi)ean  sheep  and 
goats. 

(//)  (l^soj)hagostominn  dentatum  of  the  intestines  of  swine. 


ANIMAL  PARASITES  IX  THE  INTESTINES        139 

Life  History. — Tlie  life  history  of  the  oesophagostomas, 
as  far  as  is  known,  is  as  follows:  The  ova  which  are  voided 
with  the  feces  hatch  outside  of  the  body.  When  ingested 
by  an  animal  during  the  late  summer  they  pass  from  the 
lumen  of  the  intestine  into  the  walls,  where  they  become 
encysted.  They  remain  in  the  walls  six  or  seven  months 
undergoing  in  this  time  three  successive  changes.  In  the 
early  spring  the  larvae  pass  back  into  the  bowel  lumen  and 
attain  full  development.  In  midsummer  the  females  lay 
their  eggs.  This  applies  to  all  oesophagostoma  except  the 
O.  dentatum  of  swine,  which  is  said  to  mature  within  the 
worm  nodule  in  the  wall  of  the  intestine. 

Necropsy. — In  sheep  and  cattle  there  appear  along  the 
course  of  the  small  intestine,  and  often  of  the  cecum,  nodules 
which  vary  in  size  from  a  pin-head  to  a  shoe  button  or  even 
larger.  The  nodules  vary  in  color,  the  smaller  being  black 
or  gray  and  the  larger  grayish-white.  On  incision  they  are 
found  to  consist  of  a  thick  capsule  of  connective  tissue 
surrounding  a  greenish-colored,  cheesy,  or  even  purulent 
mass.    The  small  nodules  will  be  found  to  contain  the  larvae. 

Symptoms. — Sheep  and  cattle  when  feeding  upon  low-lying 
pastures,  especially  during  the  months  of  August  and 
September,  ingest  the  larvae.  It  is  also  possible  that  they  may 
become  infested  in  stables.  As  a  rule,  if  only  a  few  nodules 
are  present  no  symptoms  of  disease  are  produced.  On  the 
other  hand,  if  large  numbers  occur  (as  many  as  six  thousand 
have  been  noted)  symptoms  of  chronic  intestinal  catarrh, 
obstinate  diarrhea,  anemia,  emaciation,  and  cachexia  are 
noted.  Nodule  disease  seems  most  fatal  in  pregnant  ewes 
on  dry  feed  during  the  early  spring  months.  As  half  of  the 
flock  can  die  in  two  or  three  months  of  the  invasion  the 
disorder  assumes  economic  importance. 

Diagnosis. — A  positive  diagnosis  can  be  obtained  only 
from  a  necropsy.  An  examination  of  the  feces  is  of  no  value, 
since  the  ova  have  not  yet  been  found. 

Treatment. — Medicinal  treatment  is  not  successful.  How- 
ever, feeding  highly  nutritious  food,  keeping  the  sheep  in 
small  flocks,  and  less  crowding  during  the  winter  season, 
especially  among  pregnant  ewes,  are  the  principal  indications 
to  be  followed. 


140  ANIMAL  PARASITES  IN   THE  STOMACH 

Echinorhynchus  Gigas  {Thorn-headed  Worm). — Echinor- 
hyiiclius  ^i^as  is  a  loiij;,  round,  white  worm  varying,  depend- 
ing on  sex,  from  (>  to  35  cm.  in  lengtli,  wliicli  itihabits  the 
intestines  of  swine.  The  head  of  this  parasite  is  armed  with 
several  rows  of  strong  hooks. 

Life  History. — Tliis  parasite  h\es  in  its  hir\al  form  encysted 
in  the  abdominal  cavity  of  the  grub  of  the  May  bug.  Even 
adult  May  bugs  may  contain  them.  Hogs  which  run  on 
woodland  pastures,  old  manure  piles,  or  clover  fields,  where 
the  May  bugs  abound,  feed  on  the  grub  or  the  adult  bugs. 
In  the  bowels  of  the  hog  the  larva^  attain  maturity  and 
fasten  themselves  by  means  of  their  hooks  to  the  mucosa 
of  the  intestinal  wall.  In  the  small  intestines  the  adult  worm 
can  produce  local  inflammation,  sometimes  even  perforation 
with  peritonitis.  The  patients  show  symptoms  of  colic  by 
grunting,  restlessness,  snapping  toward  the  alxlomen,  or 
even  other  animals.  Occasionally  in  young  ])igs  epileptiform 
convulsions  are  produced,  which  are  generally  fatal. 

Diagnosis. — A  diagnosis  can  be  made  only  by  an  examina- 
tion of  the  feces  for  the  eggs  of  the  parasite.  When  a  number 
of  pigs  are  sick  with  symptoms  of  colic,  con\'ulsions,  etc.,  a 
necrops.v  will  reveal  the  existence  of  the  worm. 

Treatment. — Treatment  is  not  very  successful,  as  the 
worms  are  hard  to  dislodge.  One  of  the  best  agents  is  oil  of 
turpentine  (oij)- 

Prevention. — Prevention  consists  in  kee])ing  swine  out  of 
woods  pastures,  manure  piles,  etc.,  and  the  destruction  of 
the  INIay  bug  and  its  grub. 

Oxyuris  Curvula  {Whip-ioorm). — This  parasite  is  found 
living  in  the  large  intestine  of  the  horse.  Erequently,  how- 
ever, it  is  found  in  the  rectum,  where  it  causes  irritation  and 
proctitis,  inducing  the  patient  to  rub  the  root  of  the  tail  and 
buttocks.  Quite  often,  as  a  result  of  the  catarrhal  inflam- 
mation of  the  rectum,  a  layer  of  white  to  yellowish  dried 
exudate  is  found  about  the  anus  and  perineiun. 

Treatment. — The  treatment  consists  in  giving  clysters  of 
linseed  oil  or  vinegar,  Bichlorid  of  mercury,  1  to  2000  in 
small  quantities  (Oj),  is  also  useful.  Large  doses  have 
])roduced  mercurialism. 


ANIMAL  PARASITES  IN  THE  INTESTINES        141 

Uncinariasis  (Dochmiasis). — Uncinaria  rarely  affect  cattle, 
altliDiigh  cases  are  reported  from  the  States  of  Florida  and 
Texas,  where  the  disorder  produced  by  them  is  known  as 
"salt  sick." 

Life  History. — The  ova  which  are  found  in  the  feces  of 
infected  animals  develop  into  embryos  within  twenty-four 
hours  under  favorable  conditions.  In  water  and  damp 
earth  they  undergo  several  changes,  so  that  after  about  one 
month  they  are  capable  of  further  development  in  the  bowel 
of  a  susceptible  host.  The  adult  worm  varies  from  3  to  8  cm. 
in  length  and  its  anterior  end  is  bent  in  the  form  of  a  hook. 

Natural  Infection. — The  infection  takes  place  among  cattle 
by  drinking  water  from  stagnant  pools  containing  the 
embryos  or  from  infested  low-lying  pastures.  Obviously, 
drought,  lack  of  proper  food  and  care,  digestive  disturbances, 
etc.,  which  reduce  the  resistance  of  an  animal,  are  contrib- 
uting causes. 

Symptoms. — In  general  the  uncinaria  produce  symptoms  of 
a  gastro-intestinal  catarrh  leading  to  anemia,  hydremia,  and 
cachexia.  One  of  the  first  symptoms  noted  is  a  morbid 
desire  on  the  part  of  the  patients  to  lick  objects.  The  cattle 
become  thin,  show  diarrhea,  often  alternating  with  con- 
stipation, and  bloating.  Symptoms  of  colic  are  not  infre- 
quent. Later  hydremia  ^develops  with  edema  of  the  region 
of  the  throat,  hydrothorax,  and  ascites.  The  patients 
usually  die  of  inanition. 

Diagnosis. — Diagnosis  can  be  made  by  a  microscopic 
examination  of  the  feces  for  the  ova.  Johne's  disease  is 
distinguished  from  it  by  the  character  of  the  diarrhea, 
which  is  more  watery  than  in  uncinariasis  and  the  presence 
of  acid-fast  bacilli  in  scrapings  from  the  anterior  portion 
of  the  rectum. 

Treatment. — Treatment  is  only  fairly  satisfactory.  In- 
tensive feeding  and  better  care  keep  up  the  strength  and 
health  of  the  patient,  greatly  assisting  the  cure.  Medicinal 
treatment  is  the  same  as  for  round-worms. 

Prevention. — Keep  cattle  away  from  infected  pastures, 
water  only  from  running  streams,  wells,  or  good  springs, 
sprinkle  the  infected  manure  with  lime  water,  and  thoroughly 
clean  and  disinfect  the  stable. 


CHAPTER  V. 
DISEASES  OF  THE  LIVER. 

JAUNDICE.     ICTERUS. 

Definition. — Jaundice,  or  icterus,  is  a  condition  due  to  tiie 
deposit  of  bile  pigment  in  the  organs  of  the  body,  especially  in 
the  skin  and  mucous  membranes.  Jaundice  is  a  sym]itom 
and  not  a  disease,  and  may  be  due  to  a  variety  of  conditions. 
From  a  pathological  standpoint  three  forms  of  jaundice  are 
distinguished:  (a)  catarrhal  jaundice,  (6)  hepatogenous 
jaundice,  and  (e)  toxic  jaundice. 

From  a  clinical  standpoint  three  types  of  jaundice  are 
differentiable:  (a)  obstructive  jaundice,  (b)  malignant 
jaundice,  and   (r)  jaundice  of  the  newborn. 

Obstructive  Jaundice. — Defijiition. — Obstructive  jaundice, 
sometimes  called  catarrhal  icterus,  is  the  commonest  form 
in  animals,  especially  dogs,  and  is  usually  associated  with  a 
gastro-intestinal  catarrh  which  iiivolves  the  duodenum, 
leading  to  a  tumefaction  of  the  mucosa  of  the  bile  ducts. 
As  a  result  the  bile  cannot  be  ])roperly  eliminated;  therefore 
some  of  it  is  resorbed  by  the  blood.  Obstruction  by  foreign 
bodies  within  the  ducts  (parasites,  rarely  gall-stones)  may 
be  a  cause.  Obviously,  tumors,  enlarged  lymph  glands,  or 
even  fecal  accumulation,  ])rovided  they  press  upon  the 
ducts,  can  have  the  same  effect.  The  icterus  seen  in  influ- 
enza of  the  horse  is  ])r()bal)l>'  the  result  of  catarrh  of  the 
bile  ducts,  although  it  may  be  in  i)art  toxemic. 

Symptoms. -Obstructive  jaundice  usually  begins  with 
symptoms  of  digestive  disturbances  (gastro-intestinal 
catarrh).  Later  there  develoi)s  a  tinting  of  the  mucous 
membranes,  skin,  and  mMue.  The  color  ranges  from  a 
lemon  yellow  (catarrhal  icterus)  to  a  deep  olive  green  in 
permanent  obstruction    (malignant   icterus).     In  the  urine 


JAUNDICE— ICTERUS  143 

the  presence  of  bile  pigment  may  be  determined  cliemically 
(Gmelin's  test).  As  no  bile  reaches  the  intestinal  tract  the 
feces  are  pale  drab  or  slate  colored,  and  usually  very  fetid. 
The  general  symptoms  are  those  of  languor,  dulness,  slow- 
pulse,  and  subnormal  temperature.  In  man  the  respirations 
may  fall  below  normal  and  xanthopia,  or  yellow  vision  may 
occvn-. 

Prognosis. — The  prognosis  in  this  form  of  icterus  is  usually 
favorable. 

Treatment. — Treatment  consists  in  regulating  the  diet 
(gastro-intestinal  catarrh)  and  the  administration  of  anti- 
catarrhal  agents,  such  as  Carlsbad  salts.  To  relieve  con- 
stipation, purgatives  (aloes,  calomel)  are  recommended. 
Pilocarpin  (gr.  iij),  followed  by  potassium  tartrate,  is  given. 

Malignant  Jaundice  {Icterus  Gravis). — Definition. — This 
form  of  jaundice  is  marked  by  its  malignancy,  and  character- 
ized anatomically  by  a  destruction  of  the  liver  cells,  with 
reduction  in  volume  of  the  organ. 

Occurrence. — Malignant  jaundice  is  a  rare  disease  in 
animals.  Occasionally  cases  are  seen  in  the  horse  and 
sheep. 

Etiology. — The  causes  are  net  well  understood.  It  has 
been  known  to  follow  phosphorus  poisoning,  feeding  lupine, 
sour  potato  peelings,  vetch  straw,  and  hay  from  flooded 
meadows.  In  some  cases  it  is  probably  due  to  a  toxin 
eliminated  during  septicemia  and  gastro-enteritis.  In  man 
there  seems  to  be  a  close  association  between  the  disease 
and  pregnancy. 

Symptoms. — The  principal  symptom  is  a  profound  icterus, 
associated  with  which  are  weakness,  coma,  sinking  of  the 
temperature,  hemorrhage  of  the  skin  and  mucous  membranes, 
and  often  a  rapid,  fatal  course. 

Prognosis. — The  prognosis  is  bad.  Death  usually  occurs 
in  about  one  week. 

Treatment. — Treatment  is  unsatisfactory.  Recommended 
are  disinfectants,  purgatives,  and  diuretics. 

Jaundice  of  the  Newborn  {Icterus  Neonatorum). — Defini- 
tion.— This  form  of  icterus,  as  the  name  indicates,  occurs  in 
animals  just  after  birth. 


114  DISEASES   OF    lUE    IJ\  ER 

Occurrence.  It  is  more  common  in  caKt-s,  altlion^li 
ocrasionally  is  met  Avith  in  foals  during  the  first  few  days 
after  birth. 

Etiology. — It  s^ems  to  have  several  different  causes: 
constii)ation,  which  pre\ents  the  discharge  of  the  meconium; 
stenosis  of  the  gall  ducts;  increased  secretion  of  bile  in  the 
first  few  days  of  life;  reduced  blood-pressure,  and  probably 
diseases  of  the  umbilical  veins. 

Symptoms. — Symptoms  are  those  of  a  catarrhal  icterus 
which  in  some  instances  is  preceded  by  gastro-intestinal 
disturbances. 

Prognosis. — The  prognosis  is  bad,  as  the  majority  of  cases 
soon  die.  Those  animals  which  do  recover  u.sually  do  so 
when  the  digestive  disturbance  is  relieved. 

Treatment. — Same  as  for  catarrhal  icterus. 


INFLAMMATION  OF  THE  LIVER.     HEPATITIS. 

Definition. — By  the  term  ]ie])atitis  we  imderstand  an  inflam- 
mation of  the  liver.  Depending  upon  the  seat  of  the  inflam- 
mation, i.  e.,  whether  in  the  liver  cells  or  interstitial  tissue,  the 
ccurse  and  tlie  anatomical  character  of  the  inflammation, 
three  clinical  forms  may  be  distinguished:  (a)  parenchy- 
matous hepatitis,  (6)  chronic  interstitial  hepatitis,  and  (c) 
jmrulent  hepatitis  (abscess  of  the  liver). 

Acute  Parenchymatous.  Definition. — This  consists  in  an 
infiannnation  of  the  liver  cells  with  cloudy  swelling  and 
fatty  infiltration  of  the  same. 

Etiology. — The  disorder  is  almost  always  a  secondary 
condition.  Primary  cases  may  be  induced  by  numerous 
toxic  substances,  such  as  spoiled  food,  poisonous  plants, 
phosphorus,  or  l)acteria  which  are  carried  to  the  \\\ev  through 
the  portal  system,  or  occasionally  through  the  umbilicus. 
In  the  latter  case  the  hepatitis  may  be  enzootic,  as  occurs 
in  ])igs  and  lambs. 

I  lepatitis  is  secondary  to  many  infectious  diseases  (septi- 
cemia, influenza).  It* may  also  be  secondary  to  poisoning 
with  j)hosphorus  or  arsenic.     In  some  instances  the  cause  is 


INFLAMMATION  OF  THE  LIVER— HEPATITIS      145 

parasitic  (distoma,  cysticercus,  sclerostoma),  which  wander 
into  the  Hver  substance. 

Necropsy. — The  Uver  is  swollen  (borders  rounded),  con- 
gested, spotted  with  dark  red  hemorrhages.  The  consistency 
is  softer  and  more  friable  than  normal. 

Symptoms. — The  symptoms  of  acute  parenchymatous  hep- 
atitis are  usually  very  vague  and  masked  by  those  of  the 
primary  disease,  to  which  it  is  secondary. 

Diagnosis. — A  diagnosis  can  rarely  be  made  during  life, 
except  in  the  dog,  where  the  symptoms  are  those  of 
weakness,  icterus  and  sensitiveness  over  the  region  of 
the   liver. 

Treatment. — Treatment  consists  in  the  administration  of" 
salts,  which  mildly  purge,  and  the  use  of  intestinal  disin- 
fectants. The  diet  should  be  regulated  by  excluding  food 
rich  in  fats. 

Chronic  Interstitial  Hepatitis  {Cirrhosis  of  the  Liver). — 
Definition. — Cirrhosis  of  the  liver  consists  of  an  inflammatory 
proliferation  of  connective  tissue  with  atrophy  of  the  liver 
cells.  Two  forms  of  cirrhosis  may  be  distinguished,  the 
hypertrophic  and  the  atrophic.  In  the  first  form,  due  to 
cellular  infiltration  and  the  increase  in  connective  tissue, 
the  liver  is  increased  in  size,  while  in  the  latter  form,  due  to  a 
shrinkage  of  the  connective  tissue,  a  marked  decrease  in  the 
size  of  the  organ  occurs.  The  consistency  of  the  liver  is  very 
hard  and  firm  and  its  surface  very  irregular  (hobnail  liver), 
or  the  surface  may  appear  granular  or  lobed  or  there  may 
be  diffuse  induration. 

Occurrence. — Chronic  interstitial  hepatitis,  while  usually 
sporadic,  in  some  instances  may  assume  an  enzootic  dis- 
tribution (Schweinburg  disease,  Xorth  Dakota  bottom 
disease),  causing  considerable  loss  among  cattle,  sheep, 
and  swine. 

Etiology. — The  cause  of  interstitial  hepatitis  in  animals  is 
unknown.  In  all  probability  it  may  be  toxic  and  due  to 
plants  of  the  senecio  group  (rag  wort),  or  it  may  be  infectious. 
In  animals  it  is  more  often  the  result  of  animal  parasitism 
(sclerostomiasis).  Congestion  of  bile  is  a  rare  cause.  Cir- 
rhosis of  the  liver  is  a  symptom  of  distomatosis. 
10 


140  DISEASES  OF  THE  LIVER 

Symptoms. — The  sytnptoms  of  the  disease  do  not  usually 
attract  attention  until  the  later  stages,  and  even  then 
they  are  rather  vague  in  animals.  In  general  they  consist 
in  symptoms  of  chronic  gastro-intestinal  catarrh,  with  a 
tendency  to  icterus.  Impaired  or  capricious  appetite, 
periodical  attacks  of  colic,  especially  after  feeding  roughage, 
symptoms  of  immobility  (stupor,  forced  movements,  vertigo), 
icteric  or  pale  mucous  membranes,  loss  of  condition,  hide- 
boundness,  and  eventually  emaciation  are  the  symptoms 
usually  noted.  In  small  animals,  and  in  large  ones  if  suffi- 
ciently emaciated,  it  is  possible  to  percuss  out  an  enlarged 
area  of  hepatic  dulness  (see  larger  works).  In  small  animals 
ascites  and  anasarca  a])pear  toward  the  end. 

Course. — The  course  is  chronic  and  extends  over  months 
and  years. 

Treatment. — The  treatment  is  usually  of  little  value, 
although  some  observers  report  temporary  improvement 
after  using  iodin  preparations. 

Purulent  Hepatitis  (Abscess  of  the  Liver). — Etiology. — Liver 
abscesses  are  not  uncommon  in  calves  and  adult  cattle,  but 
are  rare  in  horses.  They  may  originate  in  the  following 
ways:  (a)  Enterogenic  infection  due  to  pus  organisms  or  the 
necrosis  bacillus  from  an  infection  of  the  portal  system  from 
the  bowel.  (//)  Embolic  or  jjyemic  abscesses,  which  are 
formed  via  metastasis  in  strangles  or  pyemia,  (c)  Infection 
through  the  umbilicus  of  newborn  colts  and  calves,  (d) 
Traumatic  abscesses  due  to  foreign  l)odies  which  penetrate 
the  li^•er  usually  from  the  reticulum  and  more  rarely  from 
without,  (e)  Parasitic  abscesses  due  to  echinococci,  distomes, 
and  other  animal  parasites  which  have  invaded  the  organ. 

Symptoms. — The  symptoms  are  very  indefinite,  and  a 
diagnosis  is  rarely  made  during  the  life  of  the  ])atient. 
Briefly  they  consist  in  fever,  symptoms  of  indigestion,  pain 
on  palpation,  and  the  presence  of  bile  pigment  in  the  urine. 

Course  and  Prognosis. — The  course  is  chronic  and  the 
])rogn()sis  bad. 

Treatment. — Treatment  in  animals  is  of  no  avail.  In  rare 
instances  o})ening  the  abscesses  has  been  attempted,  but 
with  indifferent  success. 


THE  LIVER  FLUKE  DISEASE— DISTOMATOSIS     147 


THE  LIVER  FLUKE  DISEASE.     DISTOMATOSIS. 

Definition. — An  inflammation  of  the  liver  and  bile  ducts  due 
to  the  presence  of  trematode  parasites  of  the  genus  fasciola. 

Occurrence. — The  disease  produced  by  these  flukes  is 
commonly  known  as  "liver  rot"  and  sometimes  assumes  an 
epizootic  distribution,  particularly  among  sheep,  where  it 
causes  considerable  loss.  The  disease  is  sometimes  noted 
in  cattle,  but  rarely  attains  in  these  animals  economic 
importance.  There  are  two  forms  of  liver  fluke  in  animals: 
(1)  Distomum  hepaticum  (Fasciola  hepatica)  and  (2)  Distoma 
lanceolatum  (Fasciola  lanceolata). 

Natural  History. — The  eggs  of  Distomum  hepaticum  reach 
the  outer  world  with  the  feces.  On  damp  pastures  and  under 
the  influence  of  simimer  heat  the  embryo  is  hatched  in  about 
one  month.  They  then  enter  snails,  in  which  in  about 
four  wTeks  they  become  converted  into  sporocysts,  out  of 
which  there  develop  radiae.  From  the  radise  pass  out  the 
cercarise.  The  cercariae  swim  about  in  water  and  attach 
themselves  to  blades  of  grass,  in  which  they  become  enclosed 
by  a  sticky  substance.  The  infestation  of  the  animal  occurs 
from  eating  the  grass  or  forage  or  from  the  drinking  water 
containing  these  encysted  cercaria?.  It  is  possible  for 
infestation  to  take  place  in  the  sheepfold  either  from  green 
food  and  water  or  probably  from  dry  food.  After  ingestion 
the  parasites  pass  through  the  bile  ducts,  in  which  they 
become  sexually  mature  in  from  five  to  six  weeks.  From  the 
gall  ducts,  in  which  they  have  produced  chronic  inflammation 
and  dilatation,  they  pass  into  the  liver  substance.  Here  they 
induce  hemorrhagic  foci,  multiple  abscesses,  and  ultimately 
cirrhosis  of  the  liver.  In  rare  instances  they  may  perforate 
the  capsule  of  the  liver  or  even  the  portal  vascular  system, 
causing  phlebitis  and  thrombosis.  Sometimes  they  enter 
the  lungs,  inducing  hemorrhagic  foci,  and  encysted  worm 
nodules  may  be  found  in  the  bronchi.  From  the  lungs  they 
may  enter  the  arterial  circulation  and  pass  through  it  to  all 
parts  of  the  body.  A  passage  from  the  mother  to  the  fetus 
through  the  placental  circulation  occasionally  happens, 
which  accounts  for  their  appearance  in  newborn  calves. 


148  DISEASES  OF   THE  LIVER 

Symptoms. — In  cattle,  as  a  rule,  notwithstandinji'  the 
great  inroads  which  the  parasites  make  on  the  liver,  clinical 
symptoms  are  absent.  In  sheep,  however,  they  prodnce 
symptoms  of  a  severe  general  disease — anemia,  hydremia, 
and  ultimately  cachexia.  After  a  latent  period  of  one  or 
two  months,  and  usually  in  the  autumn,  the  infested  sheep 
begin  showing  symptoms  of  general  anemia  ("paper  skin"). 
In  the  early  winter  the  sheep  begin  to  get  thin,  show  chronic 
indigestion,  weakness,  edema  of  the  eyelids,  throat  region, 
and  ventral  jjortion  of  the  abdomen  (anasarca),  and  also 
ascites.  As  these  symptoms  may  also  occur  in  other  worm 
plagues  of  the  sheep  a  diagnosis  can  be  made  only  by  a 
necropsy  or  by  examining  the  feces  for  eggs. 

Course. — The  course  is  very  varied.  In  severe  cases  after 
a  period  of  three  months  death  ensues.  In  other  instances 
the  sheep  may  live  through  the  winter  and  die  in  the  spring, 
or  recover  after  the  emigration  of  the  flukes,  which  takes 
])lace   in   the   following   autumn. 

Treatment. — A  medicinal  treatment  is  of  no  value.  Experi- 
ence with  arsenic  and  the  various  \'ermifuges  have  given  no 
results.  The  principal  indication  is  to  strengthen  the  con- 
stitution of  the  sheep  by  intensive  feeding  and  proper  care. 

Prophylaxis. — 1'he  slice])  should  be  kept  off  infested 
pastures,  esj)ecially  land  which  lies  low.  The  sheep  should 
be  given  a  wide  range  and  kept  in  small  flocks.  Short 
pasture  is  dangerous  because  the  cercariai  are  found  close 
to  the  grass  roots.  The  egg-infested  manure  should  be 
spread  out  on  land  which  is  to  be  tilled  and  the  livers  of  the 
dead  sheep  rendered  harmless. 

ECHINOCOCCUS  DISEASE  OF  THE  LIVER. 

Definition. — An  inflannnatiou  of  the  H\cr  due  to  ;iu  in\asion 
of  the  echinococcus  parasite. 

Occurrence. — The  disease  is  quite  comnuMi  in  cattle  and 
swine  but  rare  in  oth(M'  animals. 

Natural  History.  'J'he  echinococcus  cyst  is  the  larva  of  the 
Tienia  echinococcus,  a  tai)eworin  of  the  dog.  The  segments 
of  the  tapeworm  are  voided  with  the  feces  of  the  dog,  pollut- 


ECHIXOCOCCUS  DISEASE  OF  THE  LIVER  149 

ing  stables  and  pastures  where  they  are  taken  up  by  herbiv- 
orous animals.  The  embryos  which  hatch  from  the  eggs 
in  the  stomach  and  intestines  of  the  new  host  wander  into 
the  bile  ducts  and  portal  circulation  of  the  liver  in  which 
organ  they  form  cysts,  some  of  which  contain  scpleces.  The 
cysts  vary  in  size  from  a  pea  to  a  human  head.  In  turn  if  a 
liver  containing  the  cysts  is  eaten  by  a  dog  there  develops 
in  the  intestine  of  the  dog  the  parent  tapeworm,  the  Taenia 
echinococcus. 

Two  varieties  of  Taenia  echinococcus  have  been  deter- 
mined: (1)  The  Echinococcus  unilocularis,  which  is  the  most 
common  form,  is  usually  found  in  sheep.  This  cyst  forms  either 
a  simple  cyst  or  there  may  be  adherent  to  a  principal  cyst 
secondary  or  tertiary  cysts.  (2)  The  Echinococcus  multi- 
locularis.  This  cyst  is  comparatively  rare  and  is  found  in 
cattle.  It  has  no  capsule  but  forms  in  the  liver  a  prolifer- 
ating tumor  containing  many  lacuna?  and  macroscopically 
resembles  somewhat  a  carcinoma. 

Besides  the  liver  the  echinococcus  may  invade  the  lung, 
heart,  muscle,  brain,  and  peritoneum,  or  even  occasionally 
bone  or  cartilage  (the  sternum). 

Symptoms. — The  symptoms  produced  by  the  presence  of 
this  parasite  in  the  liver  are  usually  very  vague.  In  cattle 
notwithstanding  a  great  development  of  cysts  in  the  liver  the 
animals  usually  appear  perfectly  healthy.  In  general  the 
symptoms  are  those  of  a  chronic  digestive  disturbance  and 
emaciation.  Sometimes  the  animals  show  sensitiveness  over 
the  region  of  the  liver  and  on  percussion  an  increase  in  the 
area  of  hepatic  dulness.  On  rectal  examination  sometimes 
the  enlarged  nodular  liver  may  be  felt.  In  individual  cases 
chronic  bloating  may  result,  as  in  mediastinal  tuberculosis, 
causing  compression  of  the  gullet.  In  swine  ascites  is  an 
occasional  sjTnptom.  In  very  rare  instances  the  rupture  of 
superficial  cysts  causes  fatal  peritonitis.  Recent  application 
of  the  complement-fixation  test,  using  the  fluid  contained 
in  the  cysts  as  the  antigen,  has  demonstrated  that  it  is 
valuable  in  diagnosis. 

Treatment. — No  satisfactory  treatment  for  the  disease  is 
known.    Of  great  importance  is  the  prevention  which  consists 


150  DISEASES  OF   THE  LIVER 

ill  the  (lostructiou  of  all  cchiiiococcus  cysts  found  on  post- 
mortem and  the  use  of  tseniafuges  to  drive  out  the  adult 
parasite  in  dogs. 

RUPTURE  OF  THE  LIVER. 

Defmition. — Rupture  of  the  li\-er  with  hcinorrluige  into  the 
abdominal  cavity. 

Etiology. — The  causes  are  generally  traumatic  (falls,  kicks, 
jumping,  overexertion,  etc.)  or  more  rarely  rui)ture  may 
occur  spontaneously  from  fatty  liver,  carcinoma  of  the  liver, 
or  in  primary  or  secondary  (anthrax,  ])urpura)  hei)atitis.  It 
can  result  from  amyloid  liver  and  embolism.  Phosphorus 
])oisoning  may  also  be  a  cause. 

Symptoms. — The  symptoms  of  rupture  of  the  liver  attended 
by  marked  hemorrhage  are  those  of  internal  hemorrhage,  such 
as  ])ale  mucous  membranes,  imperceptible  ])ulse,  general 
sweating  and  staggering  gait.  Death  usually  ensues  in  about 
one  to  ten  hours.  Small  hemorrhages  may  heal  under  cicat- 
rization. 

Treatment. — Treatment  is  rarely  successful  unless  the  hem- 
orrhage is  relatively  slight.  Recommended  are  subcutaneous 
doses  of  ergot  (oij).  hydrastis  or  adrenalin  (1  to  5  c.c.  of  a 
1  to  1000  solution  for  each  250  pounds  body  weight).  To 
strengthen  the  heart  oil  of  camphor  may  be  given. 

NECROSIS  OF  THE  LIVER. 

Defmition. — A  multii)le  necrosis  of  the  liver  is  a  process 
characterized  on  necropsy  by  pea-  to  walnut-sized  dry,  yellow, 
circumscribed  centres  in  the  livers  of  cattle,  swine  and  sheep. 
It  is  due  to  the  necrosis  bacillus.  Fibrinous  peritonitis  fre- 
quently attends  the  condition. 

Symptoms. — The  symptoms  are  very  vague  and  consist  in  an 
enlargement  of  the  liver,  sensitiveness  over  the  region  of  the 
liver,  high  fever,  languor,  disturbance  in  appetite,  alternating 
constipation  and  diarrhea. 

Treatment. — The  disorder  which  can  be  rarely  diagnosed 
does  not  N'ield  to  treatment. 


PARASITES  IN   THE  LIVER  151 


AMYLOID  LIVER. 

Character. — Amyloid  degeneration  of  the  liver  occurs  in 
animals  and  generally  in  connection  with  amyloid  kidney. 
It  is  usually  the  result  of  chronic  suppuration  (strangles, 
pleuritis,  abscess  of  the  liver,  etc.).  The  amyloid  liver  is 
characterized  by  its  large  size,  grayish  or  yellowish-gray  color, 
and  soft,  cheesy,  friable  consistency.  In  the  presence  of  iodin 
it  gives  a  characteristic  rich  mahogany-brown  color. 

Symptoms. — The  clinical  symptoms  are  very  indefinite. 
They  are  those  of  anemia,  cachexia,  intermittent  colic,  icterus, 
rupture  of  the  liver,  and  internal  hemorrhage. 

CARCINOMA  OF  THE  LIVER. 

Mostly  secondary  from  metastasis.  Except  in  older  dogs,  is 
rare  in  animals. 

Symptoms. — The  symptoms  are  very  vague  and  consist  in 
disturbance  in  digestion,  emaciation,  anemia,  icterus,  colic 
symptoms,  peritonitis,  rupture  of  the  liver  and  fatal  hemor- 
rhage. 

GALL-STONES.     CHOLELITHIASIS. 

Very  rare  in  animals.  They  occasionally  are  met  with  in 
cattle  and  dogs. 

Symptoms. — The  principal  symptoms  they  induce  are  colic 
(horses  and  cattle),  icterus,  and  digestive  disturbances. 

Diagnosis. — A  diagnosis  is  rarely  made  during  life. 

Treatment. — The  treatment  consists  in  the  use  of  artificial 
Carlsbad  salts. 

PARASITES  IN  THE  LIVER. 

Parasites  other  than  those  mentioned  in  the  liver  of  large 
animals  are  Cysticercus  tenuicollis,  the  cyst  of  the  tapeworm 
Taenia  marginata  of  the  dog.  These  cysts  are  usually  found 
in  sheep,  swine  and  calves.  The  Sclerostomum  bidentatum 
is  occasionally  found  in  the  liver  of  the  horse. 


CHAPTER  VI. 
DISEASES  OE  THE  rERTTOXErM. 

PERITONITIS. 

Definition. — An  inflamination  of  tlic  ])(M'itoncnim.  The  fol- 
lowiiit:;  forms  may  be  distinguished:  Erom  the  stand]){)int  of 
course,  acute  and  chronic;  extent,  circumscribed  and  diffuse. 
According  to  the  exudate  a  dry  (sicca)  and  an  exudative,  the 
hitter  being  serous,  serofi})rinous,  ])uruk'nt,  ichoric  or  hemor- 
rhagic. Specific  types  ar(>  the  tubercuhir  and  ghinders  peri- 
tonitis. 

Occurrence. — Peritonitis  is  usually  secondary  in  animals. 
The  horse  is  most  commonly  subject  to  it,  the  result  of  colics 
and  laparotomies  (cryptorchid  castration).  It  is  also  seen  in 
cattle,  due  to  puerperal  infection  and  traumatic  gastritis. 

Etiology. — The  causes  of  peritonitis  are  varied  and  from  an 
etiological  standpoint  the  following  forms  may  be  dis- 
tinguished : 

(a)  Traumatic  peritonitis  due  to  penetrating  abdominal 
wounds  from  without  or  from  rupture  and  perforation  of 
internal  organs  (stomach,  bowel,  uterus,  bladder,  spleen,  or 
liver),  or  the  bursting  of  a  mesenteric  abscess  from  within. 
]\Iost  active  in  traumatic  i)erit()nitis  are  streptococci  and  the 
colon  bacillus.  In  peritonitis  following  stomach  or  bowel 
rupture  death  may  occur  before  peritonitis  actually  develops, 
due  to  peritoneal  sepsis. 

(b)  Peritonitis  is  secondary  to  inllanmiation  of  organs  con- 
tiguous to  the  peritoneum,  the  inflanmiation  spreading  from 
the  stomach,  bowel,  uterus,  bladder,  or  liver.  Peritonitis 
may  be  secondary  to  i)leuritis. 

((')  Via  metastasis  i)eritonitis  may  develoj)  in  the  course  of 
pyemia  and  septicemia,  tuberculosis  and  glanders.  Carci- 
noma and  sarcoma  may  involve  the  peritoneum.  Peritonitis 
may  also  accomi)any  hemon-liagic  sei)ticemia  in  cattle. 


PERITONITIS  153 

Symptoms. — As  peritonitis  is  nearly  always  secondary,  its 
symptoms  are  preceded  by  those  of  the  primary  disease 
(colics,  metritis,  septicemia). 

In  acute  diffuse  peritonitis  the  following  symptoms  are 
present:  abdominal  pain  (colic)  is  prominent  especially 
toward  the  end.  The  patient  usually  does  not  roll  or  even 
lie  down  as  in  colic.  The  gait  is  stiff,  the  animal  moving  as 
one  piece,  avoiding  short  turns,  and  in  peritonitis  following 
castration  the  hind  legs  are  advanced  in  abduction,  the  animal 
walking  in  a  straddled  fashion.  The  abdominal  wall  is  tense 
and  in  many  instances  bloating  is  present.  Sensitiveness  is 
not  so  marked  in  horses  but  in  some  cases  pain  is  evinced  by 
manual  pressure. 

The  pulse  is  rapid  (SO),  irregular  and  hard  ("serous  mem- 
brane" pulse),  often  "wiry."  The  respirations  are  increased, 
shallow  and  of  the  costal  type.  With  increasing  bloating  or 
accumulation  of  abdominal  exudate,  the  dyspnea  becomes 
more  marked.  The  temperature  is  usually  high  (108°  to 
109°  F.)  but  of  no  particular  type.^  The  conjunctiva  is  highly 
reddened  in  the  early  stages  but  later  becomes  "muddy"  or 
even  cyanotic.  The  peristalsis  is  suppressed  and  usually  there 
is  obstinate  constipation  with  tenesmus.  The  urine  is  voided 
at  frequent  intervals  under  symptoms  of  strangury. 

The  general  condition  of  the  patient  is  that  of  great  prostra- 
tion. The  facial  expression  is  anxious,  and  the  body  often 
covered  with  a  cold  sweat.  Forced  movements  are  not  un- 
common (walking  in  a  circle,  etc.). 

On  rectal  examination  at  times  the  surface  of  the  peri- 
toneum may  be  felt  roughened. 

Diagnosis. — ^The  sudden  development,  the  fever,  serous 
membrane  pulse,  bloating,  stiff'  gait,  obstinate  constipation, 
and  colicky  pains  form  characteristic  symptoms  of  peritonitis, 
especially  if  they  follow  a  primary  disease  or  operation  (colic, 
castration)  to  which  peritonitis  can  be  a  sequela.  Most  valu- 
able is  the  finding  of  the  rough  and  sensitive  peritoneal  sur- 
face on  rectal  examination. 

Confusion  with  "colics"  due  to  acute  dilatation  of  the 
stomach,   tympanites,   displacements   of   bowel    or   gastro- 

1  In  rare  instances  in  perforative  peritonitis  (sepsis!)  it  is  subnormal. 


154  DISEASES  OF  THE  PERITONEUM 

enteritis  are  very  ])robal)le,  especially  if  the  pulse  becomes 
frequent  and  irre^'ular  early.  However,  the  character  cf  the 
pulse  in  j^eritonitis  is  harder  and  in  gastro-enteritis  diarrhea 
with  loud  i)eristalsis  is  present.  In  ordinary  "colics"  due  to 
fecal  stasis,  etc.  there  is  no  fever  present  and  the  ])ulse  is 
softer  in  quality. 

Chronic  or  circumscribed  peritonites  can  rarely  be  diag- 
nosed. 

Course. — In  acute  diffuse  peritonitis,  especially  when  a 
sequela  to  gastric  or  intestinal  rupture  or  the  bursting  of  a 
mesenteric  abscess  (strangles),  the  course  is  obviously  rapid 
and  fatal,  causing  death  within  twenty-four  hours.  In  less 
violent  cases  the  disease  may  last  several  days  (four  to  four- 
teen) and  lead  to  death;  or  more  rarely  become  chronic, 
lasting  for  months,  leading  to  adhesions  (adhesive  peritonitis) 
and  ascites,  causing  the  patient  to  suffer  from  periodical 
attacks  of  colic.  There  is  usually  edema  of  the  ventral  part 
of  the  abdomen. 

Prognosis. — Acute  diffuse  peritonitis  is  a  very  fatal  disease 
usuallj^  leading  to  death  in  a  few  hours.  In  mild  infections 
not  associated  with  the  perforation  of  the  stomach  or  bowel 
or  the  escape  of  pus  in  the  abdominal  cavity  death  may  not 
ensue  for  several  days.  Circumscribed  peritonitis  rarely  leads 
to  death.  Chronic  peritonitis  may  persist  for  months  or 
even  years  and  cause  adhesions  which  may  in  some  cases 
affect  digestion.  Peritonitis  due  to  penetrating  abdominal 
wounds  if  treated  according  to  surgical  principles  before  in- 
fection has  become  extensive  may  be  kept  under  control,  its 
spread  prevented  and  healing  produced. 

Treatment. — The  treatment  of  acute  diffuse  peritonitis  con- 
sists in  the  use  of  hot  ai)i)li('ations  or  of  sharj)  counterirri- 
tants,  such  as  turpentine  or  the  oil  of  mustard  in  alcohol 
(1  to  12).  To  prevent  the  spread  of  the  inflammation  by  the 
movements  of  the  intestines,  opium  (oj-ij)  should  be  given. 
Later  mild  jnirgatives  such  as  calomel  (5  j)  may  be  eni^)l()yed. 
Attem])ts,  however,  should  be  made  to  allay  constipation  by 
using  lukewarm  clysters  rather  than  through  the  use  of  drugs. 
Later  to  assist  in  the  absorption  of  ascitic  fluids  diaphoretics 
and  diuretics  may  be  tried.     Tapping  may  be  employed  and 


ABDOMINAL  HYDROPSY— ASCITES  155 

repeated  as  often  as  the  indications  warrant.  If  the  heart 
becomes  weak  oil  of  camphor  may  be  used.  This  drug  is 
also  recommended  as  an  intraperitoneal  injection  (§v)  which 
decreases  the  absorbing  power  of  the  peritoneum.  In  small 
animals  a  laparotomy  can  be  performed  and  the  abdomen 
flushed  out  with  antiseptics. 

ABDOMINAL  HYDROPSY.     ASCITES. 

Definition. — Strictly  speaking,  ascites  is  an  accumulation  of 
transudate  in  the  abdominal  cavity.  In  a  broader  sense  it 
would  include  the  fluid  exudate,  the  result  of  chronic  peri- 
tonitis. 

Occurrence. — Ascites,  while  common  in  dogs,  is  rare  in  the 
horse  and  ox.  An  exception  is  noted  in  cattle  fed  large  quan- 
tities of  turnips  or  the  residue  of  beet-sugar  factories.  In  the 
horse  ascites  is  generally  a  sjinptom  of  chronic  peritonitis  or 
interstitial  hepatitis. 

Etiology. — From  an  etiological  standpoint  three  forms  are 
recognized,  viz.,  ascites  due  to  (a)  passive  congestion,  (6) 
hydremia,  and  (c)  peritonitis. 

In  ascites  due  to  passive  congestion  there  is  a  mechanical 
disturbance  to  the  blood  circulation  in  the  course  of  chronic 
heart  (valvular  disease),  lung,  liver  (cirrhosis),  or  kidney 
disease,  leading  to  blood  stasis  in  the  vena  cava  and  portal 
veins.  A  portal  congestion  can  also  result  from  enlarged 
lymph  glands  (mesenteric!).  An  hydremic  ascites  is  most 
common  in  sheep  and  cattle,  due  to  animal  parasitism  (liver- 
fluke  disease)  and  the  hydremia  which  attends  cachectic 
conditions;  The  peritonitic  ascites  accompanies  simple 
chronic  peritonitis  and  is  sometimes  a  symptom  of  tubercu- 
losis (ox),  carcinomatosis  or  sarcomatosis  of  the  peritoneum. 

Symptoms. — The  principal  symptom  is  the  distention  of 
the  abdomen,  which  becomes  pear-shaped,  due  to  the  fluid 
contained  therein.  Thirty  to  forty  gallons  may  collect  in  the 
horse  or  ox.  Fluctuation  may  be  noted  on  palpation.  On 
percussion  of  the  lower  abdomen  a  flat  tone  is  emitted  with  a 
horizontal  upper  line  which  shifts  as  the  position  of  the 
patient  (small  animals)  is  changed.      When  tapped  a  clear 


150  DISEASES  OF   THE  PERITONEUM 

yellow  Hiiid  may  be  drawn  otl".  The  specific  gravity  of  the 
fluid  is  about  1012  and  the  albumin  about  2  to  4  per  cent. 
There  is  usually  no  fever.  If  a  large  quantity  of  fluid  is 
present  it  may  j)ress  the  diaphragm  forward  and  interfere 
with  the  action  of  the  lungs,  inducing  dyspnea.  Usually 
there  are  also  symptoms  of  the  j^rimary  disease  present  (heart 
bruits,  albuminuria,  examination  of  blood).  Often  associated 
with  ascites  are  hydrothorax,  hydrojxM-icardium,  and  ana- 
sarca (speaks  for  heart  lesions).  If  the  portal  system  alone  is 
involved  (cirrhosis  of  the  liver)  only  ascites  may  be  present. 

Diagnosis. — In  large  animals,  unless  the  ascites  is  marked 
(abdominal  distention),  due  to  the  tenseness  of  the  abdominal 
walls,  it  may  be  overlooked.  Obviously  any  condition  which 
enlarges  the  abdomen  might  be  mistaken  for  it.  Therefore 
})regnancy,  dropsy  of  the  fetal  membranes  in  cows,  distention 
of  the  bladder,  urine  accumulation  (rui)tured  bladder  in  ox), 
and  the  rare  cystic  ovary  or  tumors  (dogs)  should  be  thought 
of.  In  large  animals  rectal  exploration  (pregnancy,  distended 
bladder)  is  helpful  in  diagnosis.  An  explorative  puncture 
can  be  employed  in  cases  of  doubt.  It  not  only  reveals  the 
presence  but  the  character  of  the  fluid  (transudate,  exudate, 
urine,  etc.).  The  determination  of  the  i)rimary  disease  is 
often  difficult,  especially  when  a  lung  or  liver  disease,  as  the 
symptoms  are  vague. 

Prognosis. — I  nless  due  to  feeds  too  rich  in  water  or  hydre- 
mia the  prognosis  in  ascites  is  bad.  The  i)rimary  disease,  of 
which  it  is  merely  a  symptom,  is  usually  incurable. 

Treatment. — Treatment  is  generally  unsatisfactory.  In 
case  it  is  due  to  food  too  rich  in  water  or  too  high  an  altitude 
(brisket  disease  of  Colorado  cattle),  ])la<'ing  the  patients  on 
dry  food  or  bringing  them  to  lower  levels  are  curative.  In 
large  animals  medicinal  treatment  rarely  pays.  Diuretics, 
such  as  digitalis  (fid.  ext.  3j)  or  theobroma  (5ij),  may  be 
tried.  Arecalin  (gr.  j)  or  ])ilocarpin  (gr.  v)  are  recommended 
if  the  heart  will  stand  them.  A  good  purge  of  aloes  (5vj)  or 
Glauber  salts  (Ib.j)  is  useful. 

Tapping  the  abdomen  is  adNisable  when  dyspnea  is  dis- 
tressing the  patient.  The  operation  may  be  repeated  several 
times pro\ided  the  patient  eats  and  is  allowed  ample  nourish- 


AXIMAL  PARASITES  IN  THE  PERITONEUM      157 

ment  to  compensate  for  the  loss  of  albumin.  Omentopexy  is 
employed  in  human  practice.  This  is  the  operation  of  sutur- 
ing the  omentiun  to  the  abdominal  wall,  securing  anastomotic 
communication  between  the  portal  system  and  that  of  the 
vena  cava,  thus  producing  a  collateral  circulation  between 
the  portal  and  general  circulation. 

TUMORS  OF  THE  PERITONEUM. 

Carcinoma  and  occasionally  melanotic  sarcomas  occur  in 
the  peritoneum.  On  the  visceral  peritoneum  fibromas,  lip- 
omas, and  myxomas  are  occasionally  seen. 

Symptoms. — The  symptoms  of  tumors  of  the  peritonemn 
are  usually  too  vague  for  diagnosis.  When  generalized  car- 
cinomatosis is  present  the  patient  becomes  cachectic  and 
shows  ascites,  which  would  lead  to  the  suspicion  that  the 
peritoneum  was  involved.  In  horses  and  cattle  the  tumor 
may  sometimes  be  palpated  through  the  rectum. 

Treatment. — Treatment  is  rarely  possible,  although  benign 
tumors  might  be  removed  surgically. 

ANIMAL  PARASITES  IN  THE  PERITONEUM. 

Horse.  The  Filaria  papillosa  is  commonly  found  in  the 
peritoneum  of  horses.  The  larvjie  of  sclerostoma  also  occur. 
They  are  commonly  encapsuled,  or  more  rarely  adult  speci- 
mens are  found  free  in  the  abdominal  cavity. 

Sheep.  In  sheep  the  Cysticercus  tenuicollis  is  very  fre- 
quent and  may  lead  to  acute  peritonitis.  It  appears  as  large 
hickory  nut-  to  walnut-sized  cysts  surrounded  by  peritoneum. 
The  neck  of  the  parasite  is  inverted  into  the  cyst.  Liver 
flukes  are  also  occasionally  found  in  the  peritoneum  of  sheep. 

Sivine.  In  swine  the  Stephenurus  dentatus,  a  thread-like 
parasite,  is  not  uncommon.  ]\Iore  rarely  echinococci  and  the 
Cysticercus  tenuicollis  occur. 


PART  IV. 

DISEASES  OF  THE  REPRODUCTIVE  ORGANS. 


PUERPERAL  SEPTICEMIA. 

Definition.— A  septicemia  which  comes  from  infected 
wounds  in  the  birth  passages. 

Occurrence.— This  form  of  septicemia  which  follows  par- 
turition is  most  common  in  cows,  although  it  occurs  occa- 
sional^^ in  mares,  due  to  an  infected  wound  (tears)  in  the 
vulva,  vagina  or  uterus. 

Etiology.— The  causes  are  usually  streptococci  or  the  colon 
bacillus.  The  infection  is  carried  into  the  vagina  or  uterus 
with  the  hands,  instruments,  ropes,  etc.,  used  by  the  obstet- 
rician in  attempting  delivery.  The  result  of  the  infection  is 
usually  an  ulcerous  or  croupodiphtheritic  inflammation  of 
the  uterus  and  vagina,  with  which  is  usually  associated 
phlegmon.  A  metritis  and  perimetritis  may  at  times  develop 
and  also  a  peritonitis.  Besides  the  local  conditions  noted  we 
have  the  general  changes  due  to  septicemia  and  pyemia,  such 
as  swelling  of  the  parenchymatous  organs,  hemorrhages,  and 
metastatic  abscesses  in  internal  organs. 

Symptoms.— The  symptoms  of  puerperal  septicemia  de- 
velop within  one  to  four  days  after  parturition.  The  animal 
may  show  abdominal  pain,  straining,  and  from  the  vagina 
there  will  flow  at  first  a  blood-stained  discharge  which  later 
becomes  putrid  and  odorous.  The  lips  of  the  vulva  are 
edematous,  cold,  and  discolored.  The  temperature  is  high, 
reaching  in  the  cow  107.6°  F.;  the  pulse  capid,  irregular, 
weak;  there  is  no  appetite;  rumination  is  suppressed  and 
usually  the  patient  soon  lapses  into  a  state  of  paralysis  of  the 


1(50       DISEASES  OF  THE  REPRODUCTIVE  ORGANS 

hind  parts  and  unconsciousness.  Decubitus  develops  very 
rapidly. 

Diagnosis. — Puerperal  septicemia  might  be  confused  with 
l)arturient  i)aresis.  However,  it  may  be  distinguished  from 
the  latter  by  the  local  swelling  of  the  genital  organs,  vaginal 
discharge,  high  fever,  and  absence  of  pronounced  muscular 
paralysis.  Puerperal  septicemia  clinically  \ery  closely  re- 
sembles sapremia  due  to  retained  placenta.  In  some  cases 
a  differentiation  cannot  be  made  until  after  the  uterus  has 
been  cleaned  of  its  putrid  contents  and  disinfected.  In 
sapremia  the  patient  rapidly  recovers  once  the  cause  is 
removed. 

Course. — Puerperal  septicemia  is  very  often  fatal,  death 
occurring  within  three  or  four  days,  or  in  some  instances 
within  a  single  day.  Recovery  may  occur  in  one  or  two  weeks. 
In  some  cases  the  ])atient  is  left  in  a  state  of  chronic  pyemia 
which  leads  to  emaciation,  intermittent  fever,  chronic  vaginal 
discharge,  and  purulent  endometritis  (pyometra).  If  second- 
ary abscesses  develop  in  organs,  such  as  the  lungs,  kidneys, 
udder,  joints,  etc.,  the  course  is  prolonged.  In  horses  pur- 
pura may  be  a  sequela. 

Prognosis. — Prognosis  is  generally  unfavorable,  70  i)er  cent, 
of  the  patients  dying  in  the  acute  attack  or  from  resultant 
com])lications. 

Treatment. — Treatment  consists  in'  a  thorough  disinfection 
of  the  uterus  and  vagina  with  a  solution  of  lysol  or  creolin 
(2  per  cent.).  In  the  mare  bichlorid  of  mercury  (1  to  1000) 
may  be  employed.  The  general  symptoms,  such  as  fever  and 
weakness,  may  be  combated  symptomatically  with  alcohol 
and  \'eratrin  (gr.  ij). 

Prevention. — Prevention  consists  in  having  all  obstetrical 
instruments,  ropes,  and  the  hands  of  the  operator  disinfectetl 
before  attempting  to  assist  in  delivery. 

PARTURIENT  PARESIS.     MILK  FEVER. 

Definition. — .V non-febrile  disease  of  cattle,  swine,  and  goats 
occurring  at  or  following  parturition  and  characterized  by 
general  paralysis  and  usually  unconsciousness. 


PARTURIENT  PARESIS— MILK  FEVER  IGl 

Occurrence. — The  disorder  is  common  among  cows,  espe- 
cially valuable  dairy  cows,  which  are  heavy  feeders  and  deep 
milkers.  It  usually  occurs  at  the  acme  of  lactation  and  in 
cows  that  are  well  bred  and  in  prime  condition.  Thin  cows 
or  very  fat  cows  do  not  seem  predisposed.  When  delivery 
has  been  difficult,  parturient  paresis  is  less  apt  to  occur  than 
when  the  birth  has  been  easy  and  the  expulsion  of  the  after- 
birth prompt. 

Primipara  are  very  rarely  attacked.  Usually  it  occurs  in 
cows  from  the  third  to  the  fifth  calving. 

Etiology. — The  causes  of  parturient  paresis  are  unknown. 
The  following  theories  have  been  suggested:  (a)  auto-intoxi- 
cation from  the  uterus  or  udder  resembling  ptomaine  poison- 
ing; (b)  it  may  be  an  anaphylactic  phenomenon  or  (c)  an 
anemia  of  the  brain,  the  result  of  the  sudden  blood  flow  to  the 
udder  or  in  consequence  of  a  vasomotor  collapse. 

Symptoms. — The  symptoms  usually  begin  twelve  to  forty- 
eight  hours  after  delivery.  A  few  cases  are  recorded  where 
the  attack  came  on  during  or  even  before  the  birth.  The  prin- 
cipal symptoms  are  a  suddenly  developing  general  motor  and 
sensory  paralysis,  with  loss  of  consciousness.  After  showing 
some  symptoms  of  languor,  weakness,  and  staggering  gait 
the  cow  lies  down.  She  may  regain  her  feet  but  arises  with 
difficulty.  Finally  she  becomes  completely  paralyzed  and 
unconscious.  Often  the  patient  is  found  lying  on  her  sternum 
with  her  head  thrown  around  against  the  flank,  the  muzzle 
resting  close  to  the  udder.  In  other  cases  she  lies  fiat  on  her 
side.  The  respirations  are  slow  and  deep,  the  temperature 
normal  to  subnormal.  From  the  nostrils  a  h-mph-like  fluid 
is  discharged.  Besides  these  general  symptoms  those  of 
specific  paralyses  of  the  cranial  nerves  occur,  especially  the 
oculomotor,  trigeminal,  glossopharyngeal,  vagus,  h  j-poglossus, 
and  sometimes  the  opticus. 

The  oculomotor  paralysis  is  expressed  by  drooping  of  the 
upper  eyelids  (ptosis)  and  dilatation  of  the  pupil;  the  tri- 
geminal paralysis  leads  to  sinking  of  the  lower  jaw;  the 
glossopharyngeal  paralysis  leads  to  dysphagia;  the  vagus 
paralysis  produces  inactivity  of  the  muscles  of  the  larynx, 
leading  to  stenotic,  noisv  respirations.  It  also  increases  the 
11 


162       DISEASES  OF  THE  REPRODUCTIVE  ORGANS 

frequency  of  the  i)iilse  and  induces  a  paralysis  of  the  gullet 
and  stomach  (tymi)anites);  the  paralysis  of  the  h.N^Joglossus 
causes  prolapse  of  the  tongue  and  the  paralysis  of  the  optic 
nerve  produces  amaurosis.  As  the  sympathetic  nerve  is  also 
involved,  paralysis  of  the  brain  and  urinary  bladder  occur. 

Course. — The  course  is  very  acute.  I'ntreated  animals  may 
die  in  twelve  to  forty-eight  hours.  In  a  few  cases  the  disease 
may  take  a  subacute  course,  with  relapses.  Cases  which 
recover  from  the  ])arturient  paresis  may  die  in  about  one 
week  from  foreign-body  pnemnonia,  due  to  the  dysphagia, 
which  allows  medicines,  saliva,  and  paunch  contents  to 
enter  the  windpipe  and  lungs.  Occasionally  a  case  is  left 
with  a  chronic  paraplegia  which  may  last  for  two  or  three 
weeks,  and  end  in  recovery  or  through  decubital  gangrene 
lead  to  death.  INIastitis  and  necrosis  of  the  deep  muscles  of 
the  femur  are  rare  complications. 

Prognosis. — ^Yhile  formerly  the  mortality  was  50  per  cent., 
since  the  use  of  the  new  method  of  treatment  it  has  been 
reduced  to  10  per  cent. 

Treatment. — The  best  treatment  for  parturient  paresis  is 
that  first  suggested  by  Schmidt  of  Koldiug,  Denmark,  who 
in  the  year  1897  recommended  the  injection  of  a  solution  of 
iodid  of  potash  into  the  udder.  Later  oxygen  gas  was  em- 
ployed, and  still  later  sterile  air.  This  treatment  is  simple: 
By  means  of  a  pump  air  is  forced  through  surgeon's  cotton 
into  the  teat  canals  until  the  udder  is  well  inflated.  In  most 
instances  a  remarkal)ly  prompt  reaction  on  the  part  of  the 
patient  is  obtained.  Obviously  the  instrument,  especially 
the  teat  tube,  should  be  sterile,  the  ends  of  the  teats  thor- 
oughly disinfected  and  the  hands  of  the  operator  clean.  The 
instrument  should  be  sterilized  by  boiling  rather  than  the 
use  of  antiseptics.  In  fact,  it  is  not  advisable  to  i)ermit  anti- 
septics to  enter  the  udder,  as  mastitis  is  apt  to  result.  If  the 
sphincters  of  the  teats  are  too  weak  to  retain  the  air,  bandages 
may  be  placed  around  the  teats  to  reinforce  them.  Other- 
wise ligation  should  not  be  eni])loyed.  If  after  three  to  six 
hours  no  results  come  from  the  first  inflation  of  the  udder  a 
second  inflation  may  follow.  If  done  under  aseptic  precau- 
tions several  inflations  will  be  tolerated  by  the  mammary 
gland  without  danger  of  infection. 


ABNORMALITIES  IN  SEXUAL  DESIRE  1(33 

Whether  or  not  medicinal  treatment  in  addition  to  the 
use  of  air  is  of  vahie  is  debatable.  In  the  averaji;e  run  of 
cases  it  is  certainly  lumecessary,  except  perhaps  for  the  affect 
it  may  have  on  the  owner.  The  use  of  excitants  such  as  the 
subcutaneous  injections  of  caffein  (5j),  strychnin  (gr.  ss)  or 
arecalin  (gr.  j)  is  recommended  as  an  auxiliary  treatment. 
Giving  medicine  via  the  mouth  should  be  avoided. 


ABNORMALITIES  IN  SEXUAL  DESIRE. 

In  animals  the  sexual  desire  may  deviate  from  the  normal 
in  two  ways,  viz. :  it  may  be  abnormally  increased,  producing 
a  condition  known  as  nymphomania  in  the  female  and  saty- 
riasis in  the  male.  On  the  other  hand,  the  sexual  desire  may 
be  diminished  in  either  the  male  or  the  female.  Of  particular 
importance  is  the  nymphomania  of  cows,  mares  and  sows 
and  the  diminished  sexual  desire  of  the  male.  Occasionally 
cows  do  not  come  in  estrum  which  greatly  lessens  their 
economic  value. 

Nymphomania. — Etiology. — The  causes  of  nymphomania 
are  not  always  determinable.  In  cows  a  common  cause  is 
cystic  ovaries  or  more  rarely  tuberculosis  or  tumors  (sarcoma, 
carcinoma)  in  the  ovaries.  Diseases  of  the  uterus  such  as 
endometritis,  and  occlusion  of  the  os  may  lead  to  a  cow  failing 
to  conceive  and  therefore  a  repeated  return  of  the  period  of 
estrum.  In  other  instances  the  causes  seem  to  lie  outside 
of  the  reproductive  organs  and  probably  emanates  from  the 
spinal  cord.  Obviously  anything  which  prevents  conception 
and  renders  the  female  animal  sterile  will  produce  a  return  of 
the  period  of  heat  which  is  not  a  true  nymphomania. 

Symptoms. — In  cows  the  symptoms  are  those  of  an  exag- 
gerated estrum.  Repeated  copulation  fails  to  produce  con- 
ception. The  period  of  heat  is  also  prolonged.  The  patients 
are  nervous,  excited,  keep  up  a  continued  bellowing  and 
running  around  the  pasture  or  enclosure,  mounting  other 
animals  and  even  human  beings.  jNIilch  cows  fall  off'  in  their 
milk  and  the  milk  itself  is  of  poor  quality.  Later  the  patient 
emaciates,  the  croup  sinks  on  each  side  of  the  root  of  the  tail. 


104       DISEASES  OF  THE  REPRODUCTIVE  ORGANS 

as  ill  pregnant  animals,  and  the  neck  thickens,  resembling 
that  of  the  male. 

In  mares  there  is  a  frequent  and  almost  continuous  estrum 
followed  by  failure  to  conceive  or  abortion  if  bred.  The 
patient  is  ticklish,  nervous,  frequently  switches  her  tail, 
blinks  the  vulva,  ejecting  small  quantities  of  urine,  and  often 
becomes  vicious,  kicking  in  harness  or  biting  at  other  animals 
or  persons  who  come  near  her.  Some  mares  on  the  contrary 
show  sym])toms  of  cerebral  depression,  as  in  hydrocephalus 
(act  like  dummies).  Very  rarely  they  show  maniacal  symp- 
toms or  convulsions.  If  the  condition  persists  for  any 
length  of  time  the  patient  loses  flesh  and  shows  a  capricious 
appetite. 

In  sows  much  the  same  symptoms  occur  as  in  the  horse 
and  ox.  The  sow  is  continuously  in  heat,  does  not  conceive 
when  bred,  eats  poorly  and  consequently  loses  flesh  and 
becomes  unprofitable.  She  will  mount  contiiniously  other 
swine  and  may  become  vicious,  attacking  other  animals  or 
man. 

Treatment. — The  best  treatment  for  confirmed  cases  of 
nymphomania  is  ovariectomy  which  is  especially  valuable  in 
mares  and  cows.  In  some  instances  crushing  the  ovarian 
cysts  through  the  rectum  and  vagina  has  given  favorable 
results.  The  amputation  of  the  clitoris  which  for  a  time  was 
much  practised  in  mares  is  only  occasionally  successful. 
Placing  a  leaden  ball  in  the  uterus  is  rarely  of  benefit.  The 
use  of  narcotic  drugs  such  as  bromid  of  potash,  morphin 
and  chloral  hydrate  has  but  a  temporary  effect.  Laxatives 
are  also  employed  but  do  no  permanent  good.  In  America 
large  doses  of  salix  nigra  have  been  rccoinnicndcd.  The 
preparation  of  this  drug,  made  by  Lloyd  Brothers,  of  Cin- 
cinnati, is  highly  spoken  of.  Obviously  it  will  have  no  per- 
manent effect  upon  cases  of  nymphomania  due  to  gross 
lesions  in  the  reproductive  organs. 

Diminished  Sexual  Desire.  Etiology. — A  great  many 
causes  may  diminish  the  sexual  ai)pctite.  The  patient  may 
be  overfat,  of  phlegmatic  temperament  or  may  be  debili- 
tated from  recent  illness.  Special  causes  are  congenital  de- 
fects anil  acquired  diseases  of  the  rej>roducti\c  organs.    As 


STERILITY  165 

examples  may  be  mentioned  chronic  endometritis,  atrophy, 
degeneration  and  aplasia  of  the  testicles  or  ovaries.  Exces- 
sive sexnal  use,  especially  Avhen  the  animals  are  young,  and 
long-continued  masturbation  are  causes.  Often  the  cause  is 
purely  psychic.  P'or  instance,  many  jacks  refuse  to  cover 
mares,  although  jennets  are  served  with  promptness.  Zebra 
stallions  will  rarely  copulate  in  the  presence  of  persons, 
although  if  left  alone  with  the  female  the  coital  act  is  promptly 
committed. 

Treatment. — Diminished  sexual  desire  should  not  be  con- 
fused with  impotency  or  sterility,  although  it  may  be  a  cause 
of  these.  The  food  and  care  of  the  animal  should  be  looked 
after  and  any  apparent  discrepancies  in  these  factors  removed. 
If  the  patient  is  overfat  curtailing  the  food  ration,  allowing 
greater  quantities  of  protein  and  plenty  of  exercise  may  over- 
come the  condition.  Some  male  animals  which  have  been 
kept  isolated  or  away  from  females  for  a  long  time  seem  to 
lose  the  sexual  habit.  Very  young  stallions  which  have  never 
covered  a  mare  must  sometimes  be  encouraged  and  stimu- 
lated to  perform  the  coital  act.  Jacks  which  refuse  to  serve 
mares  can  often  be  stimulated  sexually  by  allowing  them  to 
smell  the  urine  from  a  jennet  in  heat  or  sometimes  even  by 
holding  a  jennet  where  they  can  see  her  while  approaching 
or  teasing  the  mare  to  be  served.  Certain  drugs  (aphrodis- 
iacs) will  stimulate  sexual  desire.  Cantharides  (cows  5j, 
mares  5ss;  or  the  tincture,  cattle  3v  and  mares  Siiss)  has 
long  been  employed  as  an  agent  to  promote  sexual  desire. 
Of  late  Yohimbin,  used  subcutaneously,  is  recommended. 
Its  cost  makes  it  almost  prohibitive  for  veterinary  use. 

STERILITY. 

Definition. — By  the  term  sterility  we  understand  that  the 
female  animal  is  barren  or  unable  to  produce  young. 

Occurrence. — Sterility  is  very  common,  especially  among 
well-bred  cows,  and  obviously  attains  great  economic  impor- 
tance. 

Etiology. — Sterility  is  a  symptom  and  not  a  disease.  It 
can  have,  therefore,  a  great  many  causes.    To  go  into  these  in 


106      DISEASES  OF  THE  REPRODUCTIVE  ORGANS 

detail  is  beyond  the  scope  of  this  work.  The  most  coiiimoii 
causes,  however,  are:  Disease  of  the  uterus,  often  a  chronic 
catarrh  the  result  of  retained  ])lacenta  or  abortion.  In  some 
instances  purulent  endometritis  or  chronic  catarrh  of  the 
cervix  or  vagina  may  be  the  cause.  In  other  cases  sterility 
may  be  due  to  the  ovaries  which  are  cystic  or  fibrously 
degenerated,  or  tumors,  or  an  adhesive  peritonitis  with  dis- 
placement of  the  ovary.  Furthermore,  the  uterine  tubes  may 
be  stenotic  or  occluded.  Occasionally  tuberculosis  of  the 
uterus  or  ovaries  is  a  cause. 

Symptoms. — The  symptoms  are  failure  to  conceive,  although 
the  animal  may  be  bred  repeatedly.  Occasionally  she  may 
never  come  in  heat.    In  either  case  she  remains  barren. 

Prognosis. — ()b\iously  the  prognosis  depends  on  the  cause. 
If  due  merely  to  a  catarrh  of  the  vagina  or  uterus,  which 
3'ields  to  treatment,  or  to  cystic  ovaries  and  the  cysts  can  be 
crushed  manually,  recovery  may  be  expected.  On  the  other 
hand,  if  due  to  displacement,  tumor  formation,  tuberculosis, 
atrophy  or  aplasia  of  the  ovary  the  case  is  hopeless.  The  same 
is  true  of  hermaphrodism.  Occasionally  twins  are  sterile, 
though  not  always. 

Treatment. — The  treatment  consists  in  removing  the  cause. 
In  cases  of  chronic  catarrhal  or  suppurative  endometritis  or 
vaginitis  a  thorough  disinfection  of  the  genital  tract  often 
produces  results.  If  due  to  occlusion  of  the  os  (a  rare  cause) 
dilating  the  opening  may  sufhcc.  Quite  often  reducing  the 
acidity  of  the  catarrhally  inflamed  vagina,  by  flushing  it  out 
with  a  0.5  per  cent,  solution  of  bicarbonate  of  sodium,  is 
useful.  Yeast  has  also  been  recommended.  Obviously,  on 
the  other  hand,  where  there  is  an  organic  disease  of  the  organs 
of  reproduction  all  of  these  treatments  will  fail.  Therefore 
many  cases  of  sterility  are  incurable. 

IMPOTENCY. 

Definition. — By  impotency  is  meant  the  inability  of  the 
male  to  impregnate  the  female.  There  are  two  forms  of 
impotency,  viz.:  (a)  the  animal  may  be  incapable  of  per- 
forming the  coital  act  (coital  impotency)  and  {h)  while  the 


IMPOTENCY  167 

coital  act  may  be  performed,  living,  virile  spermatozoa  are 
not  discharged  (azoospermia). 

Etiology. — The  principal  causes  of  that  form  of  impotency 
which  prevent  coition  are  diseases  and  injuries  of  the  penis, 
such  as  paralysis,  tumors  and  fractures,  or  of  the  prepuce, 
such  as  phimosis  and  inflammation  (posthitis).  In  other 
instances  the  impotency  may  be  due  to  diseases  of  the  brain 
and  spinal  cord  or  to  general  weakness  of  the  body  as  the 
result  of  chronic  disease.  In  stallions  painful  lameness  such 
as  spavin,  gonitis  or  sacral  lameness  may  be  causes. 

The  causes  of  the  second  form  of  impotency  are  usually 
due  to  diseases  or  degeneration  of  the  testicles  as  orchitis, 
aplasia,  atrophy,  tumors  or  cryptorchidism  leading  to  asper- 
mia  and  azoospermia. 

Treatment. — ^Treatment  consists  in  removing  the  cause 
wherever  this  is  possible.  Obviously  if  organic  diseases  or 
injuries  which  cannot  be  remedied  involve  the  testicles  or 
penis  treatment  is  out  of  question.  On  the  other  hand,  if  due 
to  inflammation  of  the  sheath  the  use  of  disinfectants  and 
cleanliness  will  remove  this  cause.  If  bodily  weakness  and 
general  debility  are  the  causes,  rest,  good  food  and  care  are 
all  that  is  necessary.  Young  males  should  not  be  allowed  to 
serve  too  man}^  females  within  a  short  period  of  time.  Pain- 
ful conditions  of  the  limbs  are  sometimes  removable  by  the 
application  of  surgical  treatment. 


PART  V. 

DISEASES  OF  THE  BLOOD  AND  BLOOD- 
PRODUCING  ORGANS. 


ANEMIA. 


Definition. — Anemia  is  a  condition  in  which  the  blood  is 
deficient  in  quahty  or  in  quantity.  The  deficiency  in  quahty 
may  be  a  diminution  of  the  amount  of  hemoglobin  (oHgo- 
chromemia)  or  in  the  number  of  red  corpuscles  (oligocythe- 
mia). Anemia  may  be  local,  due  to  the  fact  that  the  blood 
supply  to  a  part  is  diminished,  or  it  may  be  general.  A 
primary  and  secondary  anemia  are  also  distinguished. 

Etiology. — Ivocal  anemia  is  due  to  a  mechanical  interference 
with  the  blood  supply  to  a  part.  The  interfering  factor  may 
be  an  embolism,  tumor,  spasm,  etc.  which  impedes  the  onflow 
of  the  blood.  A  primary  anemia  is  due  to  diseases  of  the 
blood-making  organs  and  is  usually  an  independent  disease 
such  as  pernicious  anemia,  or  leukemia.  A  secondary  anemia 
develops  from  faulty  nutrition  (poor  food),  severe  hemorrhage 
or  accompanying  bacterial  animal  parasitic  or  protozoan 
diseases  such  as  tuberculosis,  distomatosis,  piroplasmosis, 
etc. 

Symptoms.- — The  symptoms  which  characterize  anemia  are 
paleness  of  the  mucous  membranes  and  skin,  loss  of  energy, 
dyspnea,  emaciation  and  hydremia  with  edematous  swellings. 
The  patient  will  also  show  rapid  pulse,  palpitation  of  the 
heart,  cystolic  heart  murmurs  and  often  fever.  An  examina- 
tion of  the  blood  shows  a  diminution  of  the  red  corpuscles 
from  one-quarter  to  one-half,  so  that  in  place  of  eight  million 


170  DISEASES  OF  THE  BLOOD 

there  may  be  only  four  or  even  two  million  per  c.mm.  The 
numl)er  of  leukocytes  and  the  form  of  the  erythrocytes 
remain,  however,  practically  normal. 

Course. — While  anemia  produced  by  a  sudden  loss  of  blood 
may  be  fatal  within  a  few  minutes,  the  course  in  most  anemias 
is  chronic,  lasting?  for  months  or  years. 

Prognosis. — The  ])ro<?n()sis  depends  upon  the  cause  of  the 
anemia.  If  the  causes  are  benign  and  removable,  such  as 
moderate  hemorrhage,  poor  food,  etc.,  proper  care  and  treat- 
ment will  rapidly  replace  the  lost  blood.  On  the  other  hand, 
if  the  cause  is  malignant  and  cannot  be  removed,  such  as 
ad\'anced  tuberculosis,  chronic  protozoan  diseases  or  general- 
ized carcinomatosis,  the  prognosis  is  bad. 

Treatment. — The  treatment  must  be  go\'erned  by  the  causes 
of  the  anemia.  AVhere  due  to  hemorrhage,  poor  food  and  the 
like  obviously  these  conditions  must  be  rectified.  When  this 
is  done  a  rapid  recovery  follows.  In  secondary  anemias  the 
patients  are  best  treated  by  allowing  plenty  of  good  food  and 
such  medicinal  blood  plastics  as  iron,  arsenic,  and  phosphate 
of  lime.  In  man  the  transfusion  of  blood  from  a  healthy 
individual  to  the  anemic  one  is  advisable.  Sometimes  good 
results  are  obtained  by  the  infusion  of  physiological  salt  solu- 
tions, which  may  be  combined  with  adrenalin,  into  the  veins 
or  rectum.  The  patient  should  be  allowed  plenty  of  drink- 
ing water  provided  there  is  no  hemorrhage  present.  Where 
the  anemia  is  secondary  to  a  malignant  disease  like  tuber- 
culosis or  cancer  the  treatment  has  only  a  temporary  effect 
and  is  not  curative. 

LEUKEMIA. 

Definition. — Leukemia  is  an  anemia  with  a  marked  increase 
in  the  number  of  leukocytes  in  the  blood.  Contrary  to  a 
simple  leukocytosis  the  course  is  chronic. 

Etiology. — Leukemia  is  evidently  a  specific  disease  of  the 
organs  which  form  the  leukocytes  such  as  the  bone-marrow, 
lymph  tissue  and  spleen.    The  causes  are  not  understood. 

Forms. — Two  forms  of  leukemia  are  now  distinguished  in 
animals,  viz.:  (a)  lymphatic  leukemia  (lymphemia)  and  (/>) 
myeloid  leukemia  (myelemia). 


LEUKEMIA  171 

(a)  Lymphatic  leukemia  is  cliaracterized  by  enlargement 
of  the  lymph  glands  and  the  presence  of  small,  uninuclear 
lymphocytes  in  the  blood. 

(b)  In  myeloid  leukemia  there  is  an  enormous  enlargement 
of  the  spleen,  the  follicles  of  which  are  hyperplastic  (lineal 
leukemia).  In  the  blood  large  numbers  of  neutrophile  poly- 
nuclear  leukocytes  occur  even  as  many  as  from  one  to  five 
hundred  thousand  in  place  of  eight  thousand  per  c.mm.  The 
erythrocytes  are  diminished  in  number  and  their  form  is 
changed.  In  the  myelogenic  leukemia  the  red  bone-marrow 
is  hyperplastic,  infiltrated  and  often  resembles  pus.  In  the 
blood  there  is  an  increase  of  the  large  uninuclear  myelocytes. 
In  both  forms  of  leukemia  anemia  is  present. 

Symptoms. — The  development  of  leukemia  is  insidious. 
Generally  the  patient  shows  lack  of  energy,  sweats  easy, 
shows  capricious  appetite,  heart  palpitation  and  rapid, 
small  pulse.  The  mucous  membranes  become  pale  even  to 
pure  white  in  color.  The  patient  grows  thin,  ev^entually 
emaciates  and  from  time  to  time  edematous  swellings  appear 
on  different  portions  of  the  body.  In  the  lymphatic  form, 
which  is  commoner  in  animals  than  in  man,  swelling  of  the 
lymph  glands  appears  symmetrically  on  both  sides  of  the 
body.  The  swellings  are  firm,  round  and  non-sensitive.  The 
lymph  glands  of  the  maxillary  space,  the  prepectoral  and 
precrural  lymph  glands  are  commonly  involved.  In  some 
cases  the  enlargement  of  lymph  glands  is  so  great  as  to  inter- 
fere with  the  function  of  organs.  Therefore  dyspnea,  roaring, 
lameness,  etc.,  result.  Occasionally  an  enlargement  of  internal 
lymph  glands  (mediastinal,  sublumbar)  leads  to  severe 
dyspnea,  fecal  retention  and  the  like. 

In  the  lineal  form  the  spleen  is  enormously  enlarged.  In 
the  horse  it  may  be  palpated  through  the  rectum  and  in  small 
animals  occasionally  a  distention  of  the  left  side  of  the 
abdomen  designates  the  enlarged  spleen.  The  liver  is  also 
greatly  enlarged,  in  one  case  in  the  horse  weighing  nearly  fifty 
pounds.  The  blood  is  pale,  stains  less  intensively  and  coagu- 
lates very  slowly.  Under  the  microscope  the  number  of  leu- 
kocytes is  greatly  increased.  In  some  instances  there  may  be 
as  many  white  as  red  corpuscles  in  the  microscopic  field. 


172  DISEASES  OF  THE  BLOOD 

The  blood  se])arates  in  coagulating  into  two  layers,  a  lower 
layer  of  red  corpuscles  and  of  violet  color  and  an  upper  layer 
of  milky  appearance,  grayish  white,  made  up  of  white  cor- 
puscles and  some  fil)rin.  The  tem])erature  usually  is  little 
changed  but  toward  the  end  often  becomes  subnormal.  In 
the  last  stages  hemorrhages  occur  in  the  conjunctiva,  gums, 
bowels,  etc. 

Diagnosis. — The  diagnosis  can  be  made  with  accuracy  only 
by  examining  the  blood  microscopically.  In  pseudoleukemia 
the  symptoms  described  also  occur  but  the  blood  shows  no 
change  in  the  number  of  white  corpuscles.  With  the  aid  of 
the  microscoj)e  the  form  of  leukemia  may  also  be  determined 
by  proper  stains. 

In  tuberculosis,  glanders  and  in  malignant  tumors  enlarge- 
ment of  lymph  glands  also  appears  but  the  distribution  of 
the  enlarged  glands  is  rarely  so  symmetrical  and  the  accom- 
panying anemia  not  so  ])ron()unced  as  in  leukemia.  Further- 
more, by  a  microscopic  examination  of  the  blood,  and  the 
application  of  the  proper  tests,  a  differentiation  from  glanders 
or  tuberculosis  can  be  made. 

Prognosis. — The  i)rognosis  in  leukemia  is  bad.  Xo  case  of 
the  disease  correctly  diagnosed  has  ever  recovered. 

Treatment. — Treatment  in  animals  should  not  be  attempted, 
as  it  will  not  lead  to  success.  In  man  arsenic,  iron  and  the 
.T-rays  have  been  used  to  prolong  life.  In  human  patients 
leukemia  has  been  known  to  last  for  twelve  years  before 
causing  death. 


PSEUDOLEUKEMIA.     HODGKIN'S  DISEASE. 

Definition. — Pseudoleukemia  is  a  chronic  disease  of  the 
blood-forming  organs  almost  identical  with  leukemia  except 
there  is  no  increase  in  the  number  of  white  blood  corpuscles. 

Occurrence. — rseudoleukemia  occurs  in  horses  and  cattle 
and  is  much  more  frequent  than  leukemia.  By  some  authori- 
ties pseudoleukemia  is  su])posed  to  represent  a  form  of 
leukemia  without  increase  in  the  mmiber  of  leukocytes.  The 
true  cause  of  pseudoleukemia  is  not  known. 


SCURVY— SCORBUTUS  173 

Symptoms. — The  symptoms  are  identical  with  those  of 
leukemia  with  the  exception  that  the  relation  of  the  red  to  the 
white  corpuscles  is  not  conspicuously  changed. 

Prognosis. — The  prognosis  is  bad. 

Treatment. — In  man  iron,  arsenic,  iodin,  and  the  .c-rays  are 
used  to  prolong  life. 

HYDREMIA. 

Definition. — Hydremia  is  a  condition  in  which  the  propor- 
tion of  the  serum  of  the  blood  to  the  corpuscles  is  excessive. 
In  cattle  and  sheep  a  severe  anemia  occurs  with  which  is 
associated  a  general  hydremia  leading  to  edema  of  the  skin 
(anasarca),  accumulation  of  transudate  in  the  abdominal 
cavity  (ascites) ,  thoracic  cavity  (hydrothorax)  and  heart  sac 
(hydropericardium) . 

Etiology. — The  causes  are  chronic  diseases  of  organs,  which 
are  usually  due  to  parasites  (liver  flukes  or  lung  and  stomach 
worms),  or  from  the  feeding  of  foods  containing  too  much 
water  such  as  slop,  the  offal  of  distilleries,  beet-sugar  factories, 
etc.  A  hyperemia  due  to  high  altitude  occurs  among  cattle 
in  the  mountainous  west  (Colorado).  The  principal  symp- 
toms of  this  disorder  are  heart  palpitation,  weak  pulse,  loss 
of  flesh,  languor,  and  edematous  swellings  particularly  under 
the  sternum.  Locally  the  condition  is  known  as  "brisket 
disease."  Removing  the  cattle  to  lower  altitudes  usually 
brings  about  a  speedy  recovery. 

HEMOPHILIA. 

Definition. — Hemophilia  is  a  marked  and  abnormal  ten- 
dency in  some  individuals  to  bleeding  or  hemorrhage.  Some- 
times the  slightest  wound  will  bleed  so  profusely  as  to  become 
serious.    The  condition  is  usually  hereditary. 

Etiology. — The  causes  are  not  known.  The  condition  is 
rare  in  animals. 

SCURVY.     SCORBUTUS. 

Definition. — Scurvy  is  a  disease  resembling  purpura,  rare 
in  animals,  although  occasionally  seen  in  dogs.     It  is  char- 


174  DISEASES  OF  THE  BLOOD 

acterized  by  a  tendency  to  bleed  from  the  gums  and  to 
hemorrhage  in  various  organs  of  the  body.  In  animals  the 
disease  is  probably  infectious.  In  man  scurvy  is  most  often 
seen  among  sailors  and  persons  who  live  upon  salted  meats 
and  canned  food  but  get  no  vegetables.  Drinking  lime  juice 
and  eating  fresh  vegetables  usually  bring  about  a  rapid  cure. 

INFECTIOUS  ANEMIA  OF  THE  HORSE. 

SwAJvip  Fever.    JIiverbottom  Disease.    Loin 
Distemper. 

Definition. — An  infectious  disease  of  horses  which  is  char- 
acterized by  being  a  specific  septicemia  accompanied  by 
intermittent  or  remittent  fever,  albuminuria  and  ultimately 
progressive  anemia.    It  is  probably  due  to  a  filterable  virus. 

Occurrence. — Infectious  anemia,  while  confined  to  infected 
areas  in  a  country,  is  wideh'  distributed.  It  occurs  on  the 
Continent  of  Europe  and  in  North  America  where  it  has  been 
reported  from  the  province  of  INIanitoba  and  the  States  of 
Minnesota,  Nebraska,  Kansas,  Missouri,  Arkansas,  Wyoming, 
Colorado,  Washington,  i\Iississip])i  and  Texas.  It  also  occurs 
in  the  Panama  Canal  Zone.  While  probably  most  prevalent 
it  is  by  no  means  confined  to  swampy  districts  but  appears 
on  high,  well-drained  lands.  Naturally  the  disease  is  con- 
fined to  the  horse,  although  other  equida^  jnay  be  infected 
artificially.  Most  of  the  cases  occur  during  the  summer  and 
early  fall.  While  it  may  appear  at  other  times  of  the  year, 
cold  weather  seems  to  cause  its  abatement.  As  the  disease 
affects  a  large  lunnber  of  horses  on  infected  farms,  rendering 
them  incapable  of  performing  work  and  causing  many  deaths, 
its  economic  importance  locally  is  very  great.  In  a  herd  of 
28  horses  used  for  railroad  construction  in  North  Dakota  in 
the  year  1908,  the  loss  from  infectious  anemia  was  17.  In 
another  reported  instance  in  the  same  State,  of  242  head  the 
loss  sustained  in  a  single  year  was  98  (40.5  per  cent.).  While 
it  is  very  probable  that  the  laity  in  swamp-fever  districts  are 
apt  to  accredit  to  this  disease  losses  in  horse  flesh  from  other 
causes,  nevertheless  it  forms  a  serious  menace  to  the  horse 


INFECTIOUS  ANEMIA   OF   THE  HORSE  175 

industry  and  should  it  become  more  wide-spread  the  financial 
loss  resulting  would  be  very  great. 

The  disease  will  remain  on  a  given  farm  for  a  number  of 
years  (10-15)  where  annually  it  causes  losses  among  the 
horses. 

Etiology. — Infectious  anemia  is  due  to  a  filterable  virus 
which  cannot  be  demonstrated  by  staining  methods  nor  by 
cultivation.  The  virus  is  contained  in  the  blood,  urine,  and 
feces  of  both  clinical  cases  of  the  disease  and  apparently 
healthy  horses.  According  to  some  authorities  the  feces, 
however,  will  not  transmit  the  disease.  It  is  very  probable 
that  the  feces  are  infectious  only  when  mixed  with  infected 
urine. 

The  disease  may  be  transmitted  by  virulent  blood  or  urine 
given  intravenously,  subcutaneously  or  orally.  Other  domes- 
ticated animals  and  guinea-pigs  do  not  seem  susceptible. 

Natural  Infection. — The  disease  seems  to  be  taken  up  through 
the  digestive  tract  in  food,  water,  stable  litter,  etc.,  which 
have  become  contaminated  with  the  urine  and  feces  of  in- 
fected animals.  On  poorly  drained  pastiu-e  fields  pools  of 
water  may  easily  become  polluted  with  the  discharges  of 
infected  horses,  especially  with  urine,  thus  serving  as  sources 
of  infection.  The  disease  does  not  seem  to  be  contagious  or 
directly  communicable.  Cases  are  recorded  where  healthy 
horses  have  been  confined  in  stables  and  mingled  freely  for 
months  with  sick  ones  without  evidence  of  any  transmission 
of  the  disease.  It  is  possible  that  patients  are  not  eliminating 
the  virus  continuously  and  during  all  stages  of  the  disease. 

Suckling  colts  are  not  infected  through  nursing  diseased 
mothers  nor  has  an  intra-uterine  infection  been  observed. 

The  disease  is  usually  introduced  into  a  community  by 
the  purchase  of  either  a  clinical  case  or  an  apparently  healthy 
horse  ("missed  case"). 

Necropsy. — In  general  the  postmortem  findings  are  those 
of  an  acute  or  chronic  septicemia.  Depending  upon  the  dura- 
tion of  the  disease  they  oft'er  great  variations.  There  are  no 
postmortem  changes  which  can  be  considered  pathogno- 
monic. The  principal  changes  noted  are:  Petechia  and 
ecchjinoses  occm-ring  under  the  serous  membranes  especially 


176  DISEASES  OF  THE  BLOOD 

of  the  epicardium  and  endocardium,  spleen  and  bowels; 
swelling  of  the  lymph  glands  which  are  usually  blood-shot; 
changes  in  the  color  and  structure  of  the  bone-marrow, 
especially  of  the  long  bones.  A  longitudinal  section  of  the 
femur  or  humerus,  for  instance,  will  show  in  the  bone-marrow 
dark  red  areas  which  are  sharply  demarcated  from  the 
yellow  portion.  In  acute  cases  there  may  be  marked  swelling 
of  the  spleen,  a  symptom  not  so  manifest  in  chronic  cases. 
The  blood  may  show  no  macroscopic  changes;  in  chronic 
cases  it  appears  of  lighter  color,  watery.  While  the  condition 
of  the  cadaver  may  be  good  in  acute  cases,  in  chronic  ones 
it  is  usually  emaciated  and  shows  edematous  swellings  of  the 
skin  of  pendant  })ortions  (sheath).  Icteric  discoloration  of 
the  tissues  is  not  rare. 

Symptoms. — The  periofl  of  incubation  after  artificial  inocu- 
lation varies  from  five  to  nine  days.  From  natural  infection 
it  is  usually  two  or  three  weeks.  Two  clinical  types  of  the 
disease  may  be  recognized:  (a)  The  acute  form  which  begins 
suddenly  with  symptoms  of  languor  and  muscular  weakness. 
The  horse  tires  easily  at  work,  may  fall  to  the  ground  in 
harness  and  must  be  assisted  to  its  feet.  Quite  often  this 
weakness  is  most  })ronounced  in  the  hind  parts  ("loin 
distemper"). 

Fever  is  a  constant  symptom,  the  temperature  reaching 
its  acme  in  two  or  three  days,  ranging  from  104°  to  1 07°  F.  The 
fever  is  of  a  remittent  or  intermittent  type  continuing  until 
the  death  of  the  patient,  periods  of  increase<l  temperature 
alternating  with  feverless  periods  lasting  one  or  two  days. 
The  i)ulse  usually  ranges  from  60  to  90,  is  soft  and  weak.  The 
heart  beat  is  often  tumultuous,  a  symptom  increased  by 
exercise. 

The  conjunctiva  appears  puffy,  swollen,  slightly  tinged  with 
yellow  and  occasionally  spotted  with  petechia^  which  are 
])rincii)ally  on  the  nictating  membrane.  There  is  usually 
slight  lacrimation.  The  nasal  mucosa  is  congested  and  shows 
petechia.'.  There  may  be  a  slight  nasal  discharge  of  reddish 
color.  The  patient  often  shows  diarrhea,  the  feces  blood- 
stained, and  a  constant  symptom  is  albuminuria,  the  amount 
of  albumin  varying  from  a  mere  trace  to  1.5  per  cent.     The 


INFECTIOUS  ANEMIA  OF   THE  HORSE  177 

albuminuria  is,  however,  not  continuous  but  usually  appears 
synchronous  with  a  rise  in  temperature.  The  appetite  in 
acute  cases,  especially  during  a  fever  attack,  is  impaired;  in 
chronic  cases  a  good  appetite  may  be  retained.  The  general 
condition  of  the  patient  rapidly  becomes  bad.  Accompany- 
ing the  febrile  attacks  there  is  usually  great  loss  of  flesh,  the 
patient  finally  becoming  extremely  emaciated. 

There  is  a  tendency  for  edemas  to  appear  on  the  limbs, 
under  the  thorax  or  ventral  portion  of  the  abdomen.  Quite 
often,  however,  these  swellings  are  absent. 

The  blood  shows  little  tendency  to  coagulate  and  the  blood- 
serum  is  discolored  yellow  or  somewhat  greenish  its  color 
varying  with  each  change  in  angle  of  observation.  There  is 
a  great  diminution  in  the  number  of  red  corpuscles  which 
in  a  period  of  two  weeks  can  be  reduced  to  two  million  or 
less. 

As  the  disease  progresses  the  animal  grows  weak,  emaci- 
ated, cachectic,  paralyzed  behind,  covered  with  decubital 
sores  and  dies  of  inanition.  Pregnant  mares  often  abort. 
The  acute  form  usually  lasts  from  one  to  four  weeks.  In 
young  colts  it  may  end  fatally  in  from  one  to  two  days. 

(6)  Chronic  type. — The  chronic  type  of  infectious  anemia 
is  characterized  by  periodical  attacks  of  fever  with  feverless 
periods  of  varied  duration  between.  Sometimes  the  fever- 
less  interval  is  only  a  few  days,  at  others  it  may  be  a  few 
weeks  or  even  months.  The  fever  attack  may  last  two  to 
four  days  or  longer.  The  rise  and  fall  of  the  temperature 
take  place  gradually.  The  pulse  is  usually  increased  when  the 
temperature  is  high  but  generally  only  slightly.  The  mucous 
membranes  in  the  early  stages  are  normal  but  later  become 
anemic.  Petechise  are  rarely  seen.  During  the  fever  periods 
the  anemia  may  temporarily  disappear.  Albuminuria  is  a 
constant  symptom  occurring  concomitant  with  a  fever  period. 
In  some  instances  diarrhea  is  noted  and  occasionally  colic. 
The  general  condition  of  the  patient  becomes  bad,  it  grows 
thin,  the  hair  loses  its  luster,  stands  on  end,  the  skin  becomes 
dry.  The  patient  is  extremely  weak,  the  tail  hangs  motion- 
less, the  sphincter  ani  relaxes  and  incontinence  of  urine  and 
feces  appear.  Quite  often  the  appetite  is  preserved  until  the 
12 


178  DISEASES  OF  THE  BLOOD 

end.  In  some  cases  the  condition  of  the  animal  is  retained  to  a 
remarkable  degree;  beyond  an  intermittent  or  remittent  fever 
the  patient  may  show  no  symptoms  for  many  weeks  or 
months.  During  the  course  of  the  disease  in  individual 
animals  many  exacerbations  and  remissions  are  noted. 

The  chronic  form  may  last  for  several  months;  in  a  few 
cases  even  for  years. 

Diagnosis. — In  some  instances  the  diagnosis  is  not  difficult; 
in  others  it  is  impossible  unless  blood  inoculations  are  made. 
Where  a  district  is  known  to  be  infected  and  the  symptoms 
of  anemia,  emaciation,  edematous  swellings,  anemic  pulse, 
extreme  weakness  and  usually  good  appetite  are  present,  a 
correct  diagnosis  can  generally  be  arri^'ed  at  without  much 
danger  of  error.  On  the  other  hand,  where  the  patient  shows 
no  anemia,  and  the  condition  remains  good,  the  diagnosis 
can  be  extremely  difficult.  Only  by  taking  the  temperature 
daily  for  a  long  period  of  time  or  by  blood  inoculations  can 
the  disease  be  determined.  The  complement-fixation  test 
has  shown  itself  to  be  of  no  value. 

Infectious  anemia  might  be  confused  with  influenza,  forage 
poisoning,  anthrax  and  sclerostomiasis.  However,  a  careful 
study  of  the  clinical  phenomena  cou])led  with  a  good  history 
(infectious  anemia  having  existed  on  the  premises)  will 
usually  make  the  differentiation  attainable. 

Course  and  Prognosis. — The  acute  form  usually  leads  to 
death  as  such.  It  is  exceptional  to  find  acute  cases  going 
over  into  the  chronic  type.  Recovery  is  very  exceptional  and 
death  may  occur  quite  unexpectedly.  The  mortality  is  over 
90  per  cent.    Apparent  recoveries  are  often  noted. 

Treatment. — A  medicinal  treatment  is  without  avail. 
Quinine,  trypan  blue,  atoxyl,  coUargol  and  arsenic  preparations 
were  found  of  no  permanent  benefit.  Absolute  rest  and  very 
intensive  feeding  will  prolong  life  and  cause  improvement  in 
many  cases.  Rest  in  the  stable,  keeping  the  temperature 
down  with  cold  baths  and  enemata,  and  arsenic  administered 
internally  have  been  recommended.  This  treatment  should 
be  continued  for  about  four  to  six  weeks.  Generally  speaking, 
however,  the  treatment  of  infectious  anemia  is  very  un- 
satisfactory. 


AZOTURIA— PARALYTIC  HEMOGLOBINURIA        179 

Prophylaxis. — The  prophylaxis  consists  in  destroying  all 
animals  diseased,  segregating  the  suspects  and  preventing 
the  food  and  water  from  contamination  with  urine.  The 
stables  should  be  disinfected  and  wet  pasture  lands  drained. 
In  the  purchase  of  new  horses,  especially  those  coming  from 
known  infected  districts,  all  anemic  animals  (pale  mucous 
membranes,  early  fatigue  at  work,  increased  heart  fre- 
quency after  slight  exercise,  etc.),  and  those  showing  albumin- 
uria should  be  rejected  or  at  least  placed  in  quarantine  for 
a  period  of  three  months.  Experiments  to  produce  artificial 
immunity  have  so  far  proven  unsuccessful. 


AZOTURIA.     PARALYTIC  HEMOGLOBINURIA. 

Definition. — An  acute  auto-intoxication  of  the  horse  char- 
acterized by  degeneration  of  certain  muscles  and  the  presence 
of  hemoglobin  in  the  urine. 

Occurrence. — ]\Iost  frequent  in  young,  well-fed  horses  accus- 
tomed to  regular  work.  The  disease  usually  follows  a  tran- 
sient rest  of  a  day  or  so  and  appears  when  the  horse  is  again 
put  to  work. 

Etiology. — The  predisposing  causes  are  heavy  feeding  dur- 
ing a  short  (two  or  three  days)  rest,  the  horse  being  used  to 
regular  work.  Exceptions,  however,  are  noted:  Horses  are 
sometimes  befallen  in  the  stable,  and  those  which  have  not 
been  rested,  may  be  attacked  in  harness.  j\Iore  rarely  are 
poorly  fed,  thin  horses  affected.  Occasionally  azoturia  may 
follow  unusually  severe  exercise  as  struggling  in  the  hobbles, 
becoming  cast  in  the  stall,  etc.  The  disease  is  more  common 
in  winter  than  during  the  hot  months  but  may  occur  any  time 
of  the  year.  The  disease  occurs  in  hot,  winterless  climates. 
Badly  ventilated,  dark,  damp  stables  are  said  to  be  predis- 
posing causes. 

The  exciting  cause  of  azoturia  is  not  known.  In  all  prob- 
ability it  will  be  found  to  be  due  to  the  formation  of  certain 
toxins  which  develop  either  in  the  muscle  or  in  the  digestive 
tract  during  rest.  These  toxins  degenerate  the  muscle  paren- 
chyma and  induce  a  dissolution  of  the  red  blood  corpuscles, 


180  DISEASES  OF  THE  BLOOD 

setting  their  coloring  matter  free.  Cold  may  assist  in  that  it 
stimulates  metabolism. 

Symptoms. — ^The  attack  usually  occurs  without  warning 
and  within  ten  to  fifteen  minutes  after  leaving  the  stable  and 
while  being  driven  on  the  street.  In  rarer  instances  several 
hours  may  elapse  before  symptoms  a])])ear.  The  patient, 
which  has  been  playful  and  lively  ])crhaps,  suddenly  becomes 
stiff  behind  or  may  knuckle  in  a  hind  fetlock.  If  the  horse 
be  forced  ahead  it  may  fall  to  the  ground,  where  it  generally 
makes  vigorous  but  ineffectual  efforts  to  regain  its  feet. 
Some  cases  do  not  fall,  however,  but  retain  their  feet;  the 
gait  is  stiff  and  the  hind  parts  not  fully  under  control.  As  a 
rule  the  patient  cannot  walk  and  is  therefore  transported 
to  the  stable  or  hospital  in  an  ambulanc-c.  When  down 
during  the  first  stages  of  the  disease,  the  patient  is  restless 
and  may  struggle  desperately  to  rise.  Quite  often  the  head, 
especially  around  the  eye,  is  contused,  the  recumbent  patient 
recklessly  throwing  its  head  against  the  street  or  the  stall 
partition.  While  the  mind  is  clear  the  face  shows  great 
anxiety,  no  doubt  due  to  pain.  The  respirations  are  increased 
and  the  whole  bod}'  dripping  with  sweat.  The  muscles  of  the 
hind  parts,  especially  the  crural  muscles,  the  quadriceps 
femoris  and  the  adductors  are  harder  than  normal  and 
swollen.  In  some  instances  the  muscles  of  the  anterior  limb 
are  involved,  especially  the  anconeous  group.  The  affected 
muscles  are  not  particularly  sensitive  and  in  a  day  or  two 
become  softer  and  relax.  The  temi)erature  in  mild  cases 
is  not  much  influenced  after  the  restlessness  subsides.  In 
severe  cases,  however,  due  to  such  complications  as  decubital 
gangrene,  great  blood  dissolution,  nephritis,  pneumonia,  etc., 
the  patient  may  show  high  fever.  The  pulse  is  high  during 
the  excitement  early  in  the  attack,  but  later  becomes  slower 
unless  comi)]icati()ns  involving  tlie  heart  muscle  set  in.  It 
is  often  50  to  GO  but  may  reach  SO  to  100. 

The  urine  is  often  retained,  distending  the  bladder.  \Miere 
drawn  it  is  found  turbid  and  dark,  the  color  ^•arying  from  that 
of  coffee  mixed  with  a  little  milk  to  an  almost  inky  blackness. 
It  is  rich  in  sediment  and  if  strained  becomes  clear  but  does 
not  lose  the  dark  coloration.     The  specific  gravity  is  high, 


AZOTURIA— PARALYTIC  HEMOGLOBINURIA        181 

the  reaction  usually  alkaline.  Albumin  is  usually  present, 
phosphate,  urates  and  some  hippuric  acid  are  generally 
found. 

The  appetite  is  usually  retained  until  serious  complications 
appear.  If  nephritis  complicates  the  case,  large  quantities  of 
albumin  appear  in  the  urine  and  uremic  spasms  and  loss  of 
consciousness  follow. 

The  blood  coagulates  readily  but  the  clot  is  not  firm  and 
the  serum  limited.  The  serum  is  usually  red-stained.  The 
quantity  of  hemoglobin  present  varies  greatly.  After  the 
sweating  has  subsided  and  the  patient  has  begun  to  drink 
freely  it  will  be  found  slightly  below  normal.  The  specific 
gravity  of  the  blood  is  normal  and  the  number  of  red  cor- 
puscles somewhat  reduced. 

Complications. — (a)  Decubital  gangrene  which  may  cause 
a  general  infection;  (b)  hypostatic  congestion  or  even  inflam- 
mation of  the  lungs;  (c)  uremia  following  nephritis;  (d) 
fracture,  especially  of  the  pelvis  and  limb  from  falling  during 
the  disease. 

Course.— In  mild  cases  where  the  patient  retains  its  feet, 
the  duration  may  be  very  short,  lasting  but  one  or  two  hours. 
Severe  cases  usually  continue  for  two  or  three  days  when  the 
patient  begins  rapidly  to  improve  or  becomes  worse  and  dies. 
While  death  may  occur  on  the  first  to  third  day,  the  patient 
usually  lives  a  week.  General  infection  is  the  commonest 
cause  of  death.  In  some  cases  a  paraWsis  of  the  quadriceps 
femoris,  adductors  or  crurals  are  sequelae  which  may  delay 
complete  recovery  for  several  months.  A  given  patient  may 
suft'er  repeated  attacks  of  azoturia  within  a  few  weeks  or 
months. 

Diagnosis. — The  cardinal  symptoms  of  azoturia  are:  (1) 
the  muscular  paralysis;  (2)  the  dark-colored  urine.  The 
history  of  the  patient  should  also  be  taken  into  consideration. 
The  following  diseases  and  conditions  resemble  it:  (a)  Colic. 
Confusion  with  colic  would  be  excusable  only  in  the  early 
stages  of  the  attack.  There  is  neither  paralysis  nor  hemo- 
globinuria in  colic. 

(6)  Injury  to  the  spinal  cord.  Here  the  paralysis  is  com- 
plete behind  the  lesion;  the  tail,  sphincters,  bladder  and 


182  DISEASES  OF  THE  BLOOD 

rectum  are  also  paralyzed.    The  skin  jwsterior  to  the  injury 
is  not  sensitive  to  pin  i>ricks.     There  is  no  heniofilobinuria. 

(c)  P'ractures  of  the  pelvis  and  posterior  limb  hones  may 
sometimes  simulate  azoturia.  This  is  also  true  of  rupture  of 
the  Achilles  tendon.  Only  a  careful  examination  of  the 
patient  will  determine  these  surgical  conditions.  The  history 
and  absence  of  hemoglobinuria  are  indicative. 

(d)  Thrombosis  of  the  posterior  aorta  and  its  branches  may 
resemble  azoturia  in  that  the  patient  falls  upcm  the  roadway, 
sweats,  etc.  However,  the  attack  is  of  short  duration  (fifteen 
minutes)  when  the  horse  gets  up  again.  By  driving  it  farther 
an  attack  can  be  brought  on  as  before. 

Pro^osis. — Mild  cases  which  do  not  "go  down"  as  a  rule 
recover.  In  the  lighter  horses  the  prognosis  seems  more 
favorable  than  in  the  heavier  breeds.  The  greater  the 
severity  of  the  attack  and  the  darker  the  urine,  generally 
speaking,  the  graver  the  prognosis.  When  the  patient  has 
not  been  properly  nursed  (frequently  turned  and  deeply 
bedded)  decubital  sores  develop  and  lead  to  fatal  septicemia. 
Nephritis  may  cause  death  in  a  few  cases.  The  mortality  is 
about  80  per  cent.  There  are,  however,  great  variations  in 
this  regard.  Some  years  the  disease  seems  more  severe  than 
others.  Not  a  few  cases  recover  from  the  azoturia  but  are 
left  lame  in  one  or  both  hind  limbs,  due  to  a  quadriceps 
paralysis  commonly  called  "  azoturia  drop."  A  rapid  atrophy 
of  the  affected  muscles  takes  place  from  which  the  patient 
usually  recovers  in  three  to  twelve  months.  The  crural 
muscles  or  adductors  may  be  similarly  affected. 

Treatment. — There  is  no  specific  treatment.  The  use  of 
drugs  is  secondary  to  proper  dietetics  and  hygiene.  The 
patient  should  be  placed  in  a  well-ventilated,  clean,  light  stall 
and  be  given  plenty  of  bedding.  It  is  advisable  to  bolster 
the  horse  with  straw  bundles  so  that  it  lies  on  its  sternum. 
Every  three  or  four  hours,  if  the  patient  lies  on  its  side,  it 
should  be  turned  over.  Where  feasible  use  slings  to  raise  the 
horse  up.  Even  if  it  cannot  rest  in  the  slings  more  than  a 
few  minutes  at  a  time,  relief  is  afforded  in  that  a  better  circu- 
lation of  the  blood  is  induced  and  a  change  of  the  bedding 
made  possible.    In  the  early  stage  when  the  patient  is  thrash- 


AZOTURI A— PARALYTIC  HEMOGLOBINURIA        183 

ing  about  a  good  deal,  an  opiate  such  as  morphin  (gr.  v 
subcut.),  chloral  hydrate  (5j  per  os)  or  cannabis  indica  (oj 
intravenously)  are  indicated.  The  bowels  should  be  moved 
by  rectal  infusions  of  water  or  by  the  use  of  arecalin  (gr.  j 
subcut.)  or  pilocarpin  (gr.  iij  subcut.).  Aloes  and  salts  are 
also  employed.  The  urine  should  be  drawn  only  if  necessary, 
best  by  pressing  the  bladder  with  the  hand,  or,  in  case  this 
does  not  suffice,  by  the  use  of  the  catheter.  The  body  should 
be  rubbed  frequently.  Hot  applications  over  the  loins  and 
croup  are  recommended.  Blisters,  however,  are  not  indicated. 
Bleeding  is  of  no  therapeutic  value,  but  can  do  no  harm. 
The  patient  should  be  given  plenty  of  water  in  which  sul- 
phuric acid  fo"^'j  to  a  pailful)  has  been  placed.  The  decubitus 
should  be  fought  off  by  frequently  shifting  the  patient  and 
by  the  use  of  astringent  strew  powders,  such  as  compound 
alum  powder,  liberally  applied.  Heart  weakness  is  com- 
bated by  using  excitants  such  as  oil  of  camphor  (§ss  subcut.) 
or  caffein  (oj  subcut.).  Alcohol  and  black  coffee  are  also 
indicated.  For  threatening  paralyses  which  may  become 
sequelae  use  strychnin  nitrate  (gr.  j  subcut.). 

The  food  should  consist  of  bran  mashes,  green  food  and 
small  quantities  of  hay. 

Prophylaxis. — Horses  accustomed  to  regular  work  should 
be  exercised  when  off  dutv  and  the  food  reduced. 


PART  VI. 
DISEASES  OF  METABOLISM. 


CHAPTER  I. 
DISEASES  OF  METABOLISM. 

DIABETES. 

Definition.— Diabetes  is  a  condition  marked  by  habitual 
discharge  of  an  excessive  quantity  of  urine.  Two  forms  of 
diabetes  are  recognized  in  veterinary  medicine,  viz.:  (a) 
Diabetes  insipidus  and  (b)  diabetes  meUitus. 

Diabetes  Insipidus.— Diabetes  insipidus  is  a  chronic  disease 
marked  bv  great  thirst  and  the  passage  of  large  quantities 
of  urine  with  no  excess  of  sugar.  The  urine  is  of  low  specific 
gravity.  Diabetes  insipidus  should  not  be  confused  with 
polyuria  which  is  transitory  and  a  symptom  of  some  irritation 
to  the  kidneys  produced  by  spoiled  food  (mouldy  oats),  and 
irritant  grasses.  During  the  stage  of  climax  in  diseases 
associated  with  high  fever  the  exudates  and  debris  of  the 
disease  pass  out  through  and  irritate  the  kidneys.  In  man 
two  forms  of  diabetes  insipidus  are  recognized  from  an 
etiological  standpoint,  viz.:  Primary  or  idiopathic  which 
appears  to  have  no  organic  basis,  and  secondary  or  sympto- 
matic in  which  there  is  evidence  of  disease  of  the  brain  or  some 
other  organ.  Whether  or  not  true  diabetes  insipidus  exists 
in  animals  is  questionable.  Polyuria  (diuresis),  however,  does 
occur  and,  as  noted,  is  a  symptom  of  irritation  to  the  kidneys 
due  to  irritant  foods.  It  may  also  attend  chronic  nephritis 
or  appear  as  the  critical  polyuria  of  such  infectious  diseases 
as  pneumonia,  pleuritis,  etc. 


180  DISEASES  OF  METABOLISM 

Diabetes  Mellitus.  Definition. — Diabetes  mellitus  is  a  dis- 
ease marked  by  the  passage  of  an  exceJisix'e  ainouiit  of  urine 
containing  an  excess  of  grape-sugar. 

Occurrence. — Except  in  dogs,  where  it  is  not  comnion,  tlie 
disease  is  extremely  rare  in  animals.. 

Etiology. — The  causes  are  not  well  understood.  Heredity, 
direct  injury,  severe  mental  shock,  nervous  strain  and  worry 
are  regarded  as  causes  in  man. 

Symptoms. — The  principal  symptoms  are  a  copious  secre- 
tion of  urine  with  increased  thirst.  The  i)atients  are  languid, 
grow  thin  but  retain  a  splendid  appetite.  A  chemical  analysis 
of  the  urine  will  show  it  to  contain  4  to  8  per  cent,  grape-sugar. 
In  the  advanced  stages  cataract  (c.  diabetica)  and  ulceration 
of  the  cornea  have  been  observed. 

Course. — The  course  of  the  disease  is  chronic,  lasting  for 
months  but  ending  fatally.  Death  may  occur  suddenly  under 
coma,  probably  due  to  an  intoxication  with  /3-oxybutyric  acid 
which  accumulates  in  the  tissues  and  blood  in  large  quanti- 
ties and  is  eliminated  in  the  urine. 

Treatment. — The  treatment  of  diabetes  mellitus  is  largely 
dietary  and  symptomatic. 

GOUT.     PODAGRA. 

Definition. — Gout  is  a  painful  constitutional  or  diathetic 
disease  with  arthritis  and  an  increase  of  uric  acid  in  the  blood. 
There  is  a  gradual  de])osition  of  chalky  material  (sodiimi 
biurate)  in  and  about  the  joints.  The  disorder  may  be  acute 
or  chronic.    In  animals  gout  occurs  only  in  birds. 

OBESITY. 

Definition. — Obesity  or  corpulence  is  an  excessive  develop- 
ment of  bodily  fat  occurring  principally  in  the  subcutis.  It 
may  be  hereditary.  In  animals  it  is  usually  due  to  high  feed- 
ing and  lack  of  exercise.  For  edible  animals  a  certain  cor- 
pulence is  desirable.  It  is  also  of  value  in  horses,  as  it  enhances 
their  appearance  and  makes  them  more  salable. 

Obesity  is  one  of  the  causes  of  sterility  in  the  female  and 


LICKING  DISEASE— PICA— ALLOTRIOPHAGY      187 

impotency  in  the  male.    In  these  cases  it  assumes  economic 
importance  and  requires  treatment. 

Treatment. — Treatment  consists  in  reducin<j  the  quantity 
and  character  of  the  food  and  ahowing  the  animal  plenty  of 
exercise.  Foods  containing  large  amounts  of  carbohydrates 
and  fats  should  be  fed  sparingly,  while  those  consisting  largely 
of  protein  may  be  allowed.  Thyroid  gland  preparations  are 
recommended  as  idiothyrin  (gr.  x-xx). 

UCKING  DISEASE.     PICA.     ALLOTRIOPHAGY. 

Definition. — Licking  disease  or  pica  is  a  perversion  of  the 
appetite  manifested  by  a  craving  for  unnatural  food.  The 
afflicted  animals  will  lick,  gnaw  and  even  eat  objects  which 
they  would  not  touch  in  health.  Associated  with  the  symp- 
toms of  perverted  appetite  are  nervous  nutritive  disturbances. 

Occurrence. — Licking  disease  is  usually  confined  to  localities 
or  even  certain  premises.  It  may  sometimes  occur  enzootic- 
ally.  It  is  most  commonly  seen  among  cattle  which  are  kept 
stabled  continuously  and  appears  especially  during  the  winter 
months.  It  is  therefore  more  common  in  Europe  than  in 
America.    Pica  is  sometimes  a  forerunner  of  osteomalacia. 

Etiology. — The  causes  of  pica  are  not  known.  In  some  out- 
breaks it  has  been  shown  to  be  due  to  spoiled  forage  and  there- 
fore a  form  of  forage  poisoning.  As  pica  is  so  frequently 
associated  with  osteomalacia  in  all  probability  it  may  have 
the  same  causes  and  may  be  the  prodromal  stage  of  the  same 
disease. 

Symptoms. — The  first  s^'mptoms  are  those  of  indigestion. 
The  appetite  is  impaired,  rumination  suppressed  and  the 
patient  is  constipated.  The  symptoms  of  perverted  appetite 
begin  gradually,  the  cattle  licking  the  walls,  partitions  and 
even  the  floor  of  the  stable  almost  continuously.  In  some  cases 
they  gnaw  or  swallow  objects  of  various  nature,  including 
indigestible  and  often  loathsome  things.  Soon  the  patients 
begin  to  lose  weight,  grow  thin  and  eventually  emaciate. 
Finally  they  become  cachectic  and  usually  die  in  a  few  months. 

Course  and  Prognosis. — The  course  is  chronic  with  exacerba- 
tions and  remissions  extending  over  several  months.    If  the 


1S<S  DISEASES  OF  METABOLISM 

hygienic  and  dietarv  conditions  are  not  clianged  the  result  is 
fatal. 

Treatment. —  If  taken  early  and  l^efore  ])ronounoed  symp- 
toms of  emaciation  apj)ear  a  change  in  the  food  and  stable 
arrangement  usually  suffices  to  cure.  The  cattle  should  be 
turned  out  on  j^asture  if  the  season  permits.  If  not  the  light, 
ventilation  and  dampness  of  the  stable  should  be  corrected 
and  a  good,  well-balanced  ration  fed.  Much  recommended  is 
apomorphin  (gr.  ij-iij)  three  times  daily  for  three  days  in 
succession  but  in  some  outbreaks  it  has  not  given  results. 

Prevention. — Keeping  the  cattle  out  of  doors,  especially  on 
well-drained  pastures  and  preventing  their  eating  food  which 
is  spoiled  will  avert  the  disease. 

WOOL  EATING. 

Definition. — Wool  eating  is  a  perversion  of  the  appetite  of 
sheep  wliich  cause  them  to  eat  each  other's  wool. 

Occurrence. — Wool  eating  is  observed  among  the  finer 
breeds  of  sheep  when  in  winter  quarters.  As  it  causes  loss  of 
wool  and  a  formation  of  wool  balls  in  the  stomach  which  may 
lead  to  death  it  attains  economic  importance. 

Etiology. — Wool  eating  is  chiefly  due  to  foods  deficient  in 
nutritive  material.  Idleness  and  habit  are  no  doubt  predis- 
posing factors. 

Symptoms. — In  a  flock  of  sheep  one  or  two  of  the  lambs 
begin  nibbling  the  wool  of  their  mothers,  ])referably  wool 
which  is  stained  with  manure  and  urine.  Soon  other  lambs 
and  finally  the  adult  sheep  take  up  the  habit.  I'sually  one 
sheep  of  the  flock  is  chosen  to  furnish  the  wool  until  the  supply 
from  this  source  is  exhausted  when  a  new  sheep  is  selected. 
I'ltimately  nearly  all  of  the  members  of  the  Hock  become  wool 
eaters.  Ordinarily  the  sheep  remain  healthy,  although  once 
in  a  while  lambs  die  from  an  occlusion  of  the  stomach  openings 
or  intestine. 

Diagnosis. — The  disease  is  easily  recognized  and  differenti- 
ated from  itchy  skin  diseases  and  the  "trotter  disease"  by 
the  fact  that  the  sheep  do  not  gnaw  their  own  fleece,  and  the 
absence  of  skin  lesions. 


CHAPTER  II. 

DISEASES  OF  METABOLISISI  AFFECTING  PIUXCI- 
PALLY  THE  BOXES. 

RACHITIS.     RICKETS. 

Definition. — Rachitis  or  rickets  is  a  disease  of  young  animals 
characterized  by  faulty  calcification  of  the  growing  bones  and 
impaired  nutrition. 

Occurrence. — Rachitis  exists  in  all  parts  of  the  world  but  is 
much  more  common  in  Europe  than  in  America.  It  is  chiefly 
seen  among  young  swine  and  dogs. 

Etiology. — The  real  cause  of  rachitis  is  unknown.  Want  of 
sunlight,  impure  air,  confinement  and  lack  of  exercise  are  no 
doubt  important  perdisposing  factors.  Several  theories  have 
been  advanced  to  explain  the  etiology  of  the  disorder.  Briefly 
stated  they  are  the  following: 

(a)  Infection  producing  a  parenchymatous  osteitis.  The 
sometimes  enzootic  occurrence,  postmortem  changes  and  a 
similarity  to  the  osteitis  of  phosphorus  poisoning  lend  to 
this  theory  some  support. 

(b)  Inanition  due  to  feeding  foods  wanting  in  lime  such  as 
potatoes,  sour  milk,  bran,  etc.  Rachitis  has  been  experi- 
mentally produced  in  young  animals  by  feeding  them  foods 
poor  in  lime. 

(c)  A  disturbance  in  metabolism  which  induces  an  increase 
in  the  elimination  of  lime  from  the  body  and  a  lessening  of 
the  amount  of  lime  to  the  bones. 

Necropsy. — Postmortem  changes  in  rachitis  are  confined 
largely  to  the  epiphyses.  They  consist  in  a  chronic  h\T3er- 
emia  and  inflammation  of  the  bone  with  abnormal  prolifera- 
tion of  the  cartilages  of  the  epiphyses.  The  quantity  of  lime 
contained  in  the  bone  is  deficient.  As  a  result  of  the  pro- 
liferation the  epiphyses  become  overdeveloped,  the  cartilage 
formed  being  relatively  too  great  in  proportion  to  the  bone. 
Consequently  the  epiphyses  are  enlarged,  distorted  and  the 


190  DISEASES  OF  METABOLISM  OF  BONES 

shafts  of  the  bone  bent.  The  periosteum  also  proliferates, 
form  in  <;  jKTiosteal  enlargements. 

Symptoms. — The  symptoms  of  rachitis  are  those  of  de- 
formity of  the  bone  such  as  enlargement  in  the  region  of  the 
joints  and  bending  of  the  shafts  particularly  of  the  bones  of 
the  extremities.  The  patient  therefore  appears  coarse- 
jointed,  bow-legged,  or  on  the  other  hand,  cow-hocked  or 
knock-kneed.  The  deformity  may  also  involve  the  back, 
causing  lordosis  (sway  back)  or  kyphosis  (roach-back)  or 
scoliosis  (bent  sideward).  Tlie  pelvis  may  also  be  deformed 
and  the  bones  of  the  face  thickened  and  distorted.  As  usually 
a  chronic  rhinitis  attends  the  facial  deformity  there  is  nasal 
discharge  with  wheezy  respirations.  In  Germany  this  form 
of  rachitis  is  spoken  of  as  the  "sniffle  disease."  Along  the 
course  of  the  ribs  at  their  cartilaginous  unions  appears  a  row 
of  nodules.  These  are  spoken  of  as  the  "rosary."  Occasion- 
ally rickets  affects  the  phalangeal  articulations,  causing  ring- 
bone-like enlargements.  The  patients  usually  remain 
stunted,  grow  pot-bellied  and. are  unthrifty.  They  are  quite 
often  stiff  and  lame.  The  shedding  of  the  milk-teeth  is  post- 
poned, teeth  diseases  are  common  and  eczemas  of  the  skin 
frequent.  While  some  of  the  young  animals  retain  their 
flesh,  as  a  rule  they  grow  thin  and  emaciated. 

Prognosis. — The  disease  is  rarely  fatal  but  often  leaves  the 
patient  unthrifty  and  more  or  less  deformed. 

Treatment, — One  of  the  commonest  treatments  for  rachitis 
in  animals  is  phosphorus.  It  should  be  given  in  the  form  of 
the  oil  of  phosphorus  in  sm;ill  doses  (H.  &  C.  gr.  ^-f  and  S. 
gr.  Y2).  F'or  small  animals  pills  (gr.  yI-^)  may  be  substituted. 
Powdered  carbonate  of  lime  which  may  be  fed  with  milk  is 
also  recommended.  I^sually,  unless  the  disease  has  advanced 
too  far,  turning  the  animal  out  to  ])asture  and  allowing  j)lenty 
of  good  luitritious  food  suffice  not  only  to  check  but  cure  it. 

OSTEOPOROSIS.     OSTEOMALACIA. 

Definition. — Osteoporosis  is  a  disease  marked  by  increased 
softness  of  the  bones  so  that  they  become  frangible  and  brittle 
in  consequence  of  a  resorption  of  the  lime  content. 


OSTEOPOROSIS— OSTEOMALACIA  191 

Occurrence. — The  disease  is  not  uncommon  among  horses  in 
certain  regions  of  the  United  States.  Along  the  river  valleys 
of  the  ^Middle  West  numbers  of  cases  occur.  On  the  higher 
ground  and  especially  in  the  limestone  districts  it  is  of  rare 
occurrence.  It  is  probably  more  frequently  seen  among  citj^ 
than  country  horses.  Cattle  are  also  affected,  especially  dairy 
cows.  In  Europe  the  disease  seems  most  common  among 
cattle.  It  is  occasionally  seen  in  sheep  and  swine.  Osteo- 
porosis is  a  disease  of  adults  resembling  rachitis  in  the  young 
animals. 

Etiology. — The  causes  of  osteoporosis  are  not  well  under- 
stood. It  is  probably  due  to  infection,  as  the  anatomical 
changes  present  in  the  affected  bones  are  of  the  character  of 
infectious  inflammation.  Predisposing  causes  are  pregnancy, 
excessive  lactation  in  cows,  lack  of  lime  in  the  food  and  soil, 
darkness,  dampness  and  poor  ventilation  in  the  stables. 

Necropsy. — The  postmortem  changes  consist  in  an  inflam- 
matory hyperemia  with  decalcification  and  softening  of  the 
bone  and  marked  dilatation  of  the  Haversian  canals.  The 
bones  afi'ected  are  brittle  and  fracture  spontaneously.  They 
are  also  enlarged,  extremely  light  in  weight,  the  cortical  sub- 
stance abnormally  thin  and  the  medullary  cavity  greatly 
increased.  The  medulla  appears  as  a  reddish  gelatinous  mass. 
The  bones  chiefly  invoh'cd  are  the  pelvis,  femur,  facial  bones 
and  mandible.  Howe^'er,  it  may  afi^ect  any  bone  of  the 
skeleton.    Healed  fractures  are  not  uncommonly  noted. 

Symptoms. — While  in  some  cases  the  affection  of  the  bones 
is  preceded  by  digestive  disturbances  and  s\Tnptoms  of  viti- 
ated appetite  ("licking  disease"),  most  commonly  the  first 
symptoms  are  disturbance  in  locomotion,  the  patient  becom- 
ing lame  or  stiff  and  experiencing  diflSculty  in  getting  up  or 
lying  down.  If  the  maxillae  are  involved  there  may  be  diffi- 
culty in  mastication.  Quite  commonly  the  horse  is  thought 
to  be  suffering  from  rheumatism  which  usually  affects  the 
stifle  or  fetlock-joints.  After  rest  the  symptom  of  lameness 
may  disappear  to  recur  again,  but  in  a  different  joint,  when 
the  animal  is  returned  to  work.  In  other  cases  the  owner 
complains  of  the  horse  eating  slowly  and  losing  flesh  and 
requests   that  its  teeth  be  dressed.     In  advanced  cases  a 


\\)'2  DISEASES  OF  METABOLISM  OF  BONES 

prominent  symptom  is  enlargement  of  one  or  both  nmii  of 
the  lower  jaw  or  a  bulging  of  the  })ones  of  tlie  face  ("l)ig 
head").  Later  the  patient  becomes  more  and  more  emaci- 
ated, the  gait  stiff,  the  flank  tucked  and  finally  remains 
recumbent  and  unable  to  regain  its  feet  without  assistance. 
Spontaneous  pelvic  and  limb  bone  fractures  are  common  in 
cattle  and  goats  and  are  not  rare  in  horses,  especially  if  cast 
for  an  operation  (castration)  when  fracture  of  the  femur  or 
spinal  column  often  results.  More  rarely  the  Achilles  tendon 
tears  loose  from  its  attachment  to  the  os  calcis. 

Diagnosis. — Until  enlargements  of  the  bone  or  spontaneous 
fractiu-es  occur  the  diagnosis  is  difficult.  In  the  horse  in  all 
cases  of  obscure  lameness  resembling  rheumatism,  osteoporosis 
should  be  thought  of.  In  cattle  pica  or  licking  disease  is  a 
common  forerurmer.  Later  symptoms  of  painful  mastication, 
emaciation,  difficulty  in  rising  from  a  recumbent  position, 
stift'ness  of  gait,  tucked-up  abdomen  and  enlargement  of  the 
maxillse  appear  which  are  indicative  of  the  disorder.  In 
districts  where  the  disease  is  enzootic  obviously  the  diagnosis  • 
is  not  so  difficult  as  when  a  sporadic  case  is  met  in  a  section 
where  osteoporosis  is  rare. 

Prognosis. — Advanced  cases  are  hopeless  and  should  be 
destroyed.  If  able  to  walk  they  are  often  rested,  which 
ameliorates  the  condition,  and  sold,  but  usually  when  returned 
to  work  they  again  grow  worse.  Sometimes  trans])lanting 
the  case  to  a  district  where  the  disease  is  not  enzootic  is  fol- 
lowed by  good  results.  The  better  the  care  and  food  and  the 
lighter  the  work,  as  a  rule,  the  longer  the  patients  last. 

Course. — The  course  is  chronic  and  extends  from  three 
months  to  two  years  from  the  time  the  diagnosis  is  made. 

Treatment. — The  principal  thing  in  the  treatment  is  to 
change  the  environment  and  food  of  the  patient.  Where  it  is 
not  possible  to  remove  the  animal  to  another  district  feeding 
alfalfa,  alfalfa  feed  and  molasses  and  alfalfa  hay  have  been 
of  great  benefit.  Medicinal  treatment  is  o'f  little  value. 
Phosphate  of  lime  in  the  form  of  bone  meal  is  useful.  Or 
ph()si)horus  (gr.  ^-f )  in  oil  is  recommended.  For  symptoms 
of  "licking  disease"  in  cattle  the  hydrochlorid  of  apomorphin 
(gr.  ij-iij  subcutaneously)  is  advised. 


PART    VII. 
DISEASES  OF  THE  ORGANS  OF  LOCOMOTION. 


MUSCULAR  RHEUMATISM. 

Definition. — ]\Iusciilar  rheumatism  is  a  form  of  myositis. 

Occurrence. — ]Miiscular  rheumatism  is  not  common  in  ani- 
mals. In  large  animals  it  is  most  frequent  in  horses  and 
cattle. 

Etiology. — The  causes  of  muscular  rheumatism  are  un- 
known. Cold  and  dampness  combined  are  important  but 
probably  only  predisposing  factors.  In  all  probability  the 
immediate  cause  is  either  an  infection  or  an  intoxication, 
although  the  absence  of  fever  and  localization  in  individual 
muscles  rather  speaks  against  this  theory. 

Necropsy. — On  necropsy  the  muscles  attacked  are  hyper- 
emic,  hemorrhagic,  and  show  serous  exudate  and  cellular 
infiltration.  In  some  cases  there  is  cloudy  swelling  and  fatty 
degeneration  of  the  muscle  fibers.  In  chronic  cases  a  prolif- 
eration of  connective  tissue  occurs  in  the  muscles  attacked. 

Symptoms. — Characteristic  of  rheumatism  is  a  suddenly 
appearing  painful  condition  of  certain  muscles  which  usually 
follows  exposure  to  cold.  There  is  a  tendency  for  the  pain 
to  shift  from  one  muscular  group  to  another.  The  inflamma- 
tion disappears  often  as  suddenly  and  mysteriously  as  it 
came  but  there  is  always  a  tendency  to  relapses.  On  palpa- 
tion the  affected  muscles  feel  tense  and  are  very  sensitive. 
Depending  upon  the  location  of  the  inflammation  different 
forms  of  rheumatism  are  distinguished  clinically: 

(a)  Shoulder    rheumatism    (omalgia)    which    affects  ^  the 
biceps,   brachiocephalic   and    the    supra-    and    infraspinati 
muscles  causing  in  horses  shoulder  lameness  of  the  swinging- 
leg  tvpe. 
13 


194     DISEASES  OF  THE  ORGANS  OF  LOCOMOTION 

(6)  Lumbago.  lUieumatism  of  the  muscles  of  the  loins, 
particularly  of  the  psoas  group,  producing  paraplegia  in  the 
horse  characterized  by  stiffness  of  the  back  and  weakness  or 
paralysis  of  the  hind  parts. 

(c)  Torticollis.  A  rheumatic  torticollis  (myalgia  cervicalis) 
produces  a  stiffness  and  bending  of  the  neck.  The  splenius, 
trapezius  and  brachiocephalic  muscles  are  principally 
involved. 

(d)  Intercostal  rheumatism  which  produces  pleurodynia. 
Pleurodynia   in   horses   frequently   follows   long   railway 

journeys.  It  is  characterized  by  dyspnea  and  sensitiveness  of 
the  intercostal  muscles. 

Among  other  locations  for  rheumatism  may  be  mentioned 
the  region  of  the  hip  (hip  lameness),  masseter  muscles  (dis- 
turbance in  mastication)  and  abdominal  muscles  (constipa- 
tion). Sometimes  muscular  rheumatism  is  generalized,  affect- 
ing practically  all  of  the  muscles  of  the  body  (polymyositis). 
If  the  case  is  severe  and  attended  by  fever,  death  may  ensue. 
Frequently  as  the  result  of  chronic  rheumatism  the  animal  is 
left  permanently  lame  in  the  shoulder  or  back. 

Treatment.-  Rlieumatism  is  usually  treated  by  local  appli- 
cations such  as  massaging  the  affected  muscles  with  soap 
liniment  or  by  ap])lying  heat.  To  relieve  intense  pain  nar- 
cotics are  useful.  Preparations  of  salicylic  acid  or  salicylate 
of  soda  (3ij)  are  of  some  value.  For  chronic  rheumatic 
shoulder  lameness  the  following  prescription  is  recommended : 

^ — Verjitrin gr.  vij 

Alcohol  diluti 5ij 

M.  f.  sol. 

Sig. — Inject  5  c.c.  cvory  twelve  liours  sul)cut.  over  region  of  shoulder. 

ARTICULAR  RHEUMATISM. 

Definition. — Articular  rheumatism  is  undoubtedly  an  in- 
fectious disease.  It  affects  the  joints,  ])n)(hi('ing  in  them  a 
serous  or  serofibrinous  inflammation. 

Etiology. — While  the  causes  are  not  known  \"ery  probably 
staphylococci  and  streptococci  are  the  chief  offenders.  Cold 
is  never  more  than  a  predisposing  cause.    The  germs  enter 


ARTICULAR  RHEUMATISM  195 

the  blood  either  through  the  throat  (in  man  the  tonsils)  or 
in  cattle  through  the  puerperal  uterine  mucosa.  The  post- 
mortem lesions  are  those  of  a  serous  and  serofibrinous 
arthritis  which  in  chronic  cases  develops  into  an  arthritis 
chronica  deformans. 

Symptoms. — Articular  rheumatism  is  rare  in  animals  as 
compared  with  man.  Cattle  are  frequently  attacked,  horses 
rarely.  The  most  important  symptoms  are  found  in  the 
joints,  tendon  sheaths,  and  the  heart.  The  joint  symptoms 
usually  begin  suddenly  with  a  painful,  hot,  swelling  of 
one  or  more  joints  accompanied  by  severe  lameness  or  ina- 
bility to  stand.  The  joints  most  commonly  affected  are  the 
stifle,  fetlock,  hock  and  front  knee.  One  peculiarity  of  the 
arthritis  is  the  tendency  to  shift  suddenly  from  one  joint  to 
another  and  the  occurrence  of  relapses.  The  tendon  sheaths 
in  the  neighborhood  of  the  affected  joints  are  frequently 
involved,  particularly  the  sheaths  of  the  perforans  and  per- 
foratus,  a  painful,  hot,  fluctuating  swelling  appearing  along 
the  com"se  of  the  tendons.  Endocarditis  is  a  common  com- 
plication and  is  therefore  very  characteristic  of  this  form  of 
rheumatism.  Through  an  ulcerous  endocarditis  death  may 
occur  suddenly.  Usually,  however,  it  appears  as  a  verrucous 
endocarditis,  leading  to  valvular  disease  of  the  heart.  The 
temperature  is  elevated,  appetite  and  rumination  suppressed, 
which,  together  with  the  fever  and  pain,  lead  to  rapid 
emaciation.  Rare  complications  are  metastatic  pleuritis, 
peritonitis  and  pericarditis. 

Diagnosis. — Articular  rheumatism  may  be  confused  with 
any  other  arthritis.  INlost  commonly  it  is  mistaken  for  trau- 
matic arthritis.  However,  in  these  cases,  unless  suppurative, 
there  is  no  fe\'er  and  no  general  disturbance.  Tubercular 
arthritis,  which  is  more  common,  affects  only  one  joint  and 
is  usually  associated  with  tuberculosis  of  other  organs.  In 
adults  osteomalacia  and  in  young  animals  rachitis  should  be 
thought  of.  Here,  however,  other  symptoms  of  these  dis- 
eases are  also  present,  the  process  is  less  acute,  does  not  shift 
and  usually  several  animals  are  similarly  attacked  in  a  herd. 

Course. — While  some  cases  heal  in  two  or  three  weeks  there 
is  always  a  tendency  to  relapse.     The  course  in  articular 


190     DISEASES  OF  THE  ORGANS  OF  LOCOMOTION 

rheumatism  in  animals  is  usually  chronic  and  the  prognosis 
unfavorable.  The  disease  generally  lasts  several  months  with 
exacerations  and  remissions.  Many  of  the  patients  unable  to 
stand  die  of  decubitus.  Others  which  recover  from  the  acute 
attacks  are  left  with  an  incurable  deforming  arthritis  with 
contracture  and  anchylosis  of  the  joint  and  great  muscular 
atrophy. 

Treatment. — As  a  specific  treatment  for  articular  rheuma- 
tism salicylate  of  soda  has  been  highly  reconnnended.  It 
should  be  given  in  very  large  doses.  In  the  horse  a  daily  dose 
may  be  as  high  as  three  ounces,  usually  given  in  one-ounce 
doses,  three  times  daily.  Other  remedies  are  acetanilid  (Bj) 
and  salol  (5j)-  Local  apjjlications  of  heat  to  joints  relieve 
pain  and  assist  somewhat  in  resorption.  Antiphlogistin  is 
useful  in  this  regard  where  it  can  be  applied. 

TRICHINOSIS. 

Definition. — A  disease  of  swine  and  more  rarly  of  other 
animals  due  to  the  presence  of  the  larvjp  of  the  Trichina 
spiralis.  This  parasite  is  harbored  by  swine  in  both  the  adult 
and  larval  forms.  The  adult  worms  live  in  the  boAvels,  the 
larxic  ill  the  nuiscles. 

Occurrence. — I'richina  are  very  common  in  swine.  Probably 
5  per  cent,  of  American  hogs  harbor  the  parasite.  Occasion- 
ally outbreaks  of  trichinosis  occur  in  man  from  eating  the 
flesh  of  the  hog  which  has  not  been  thoroughly  cooked. 

Mode  of  Infestation. — Swine  are  generally  infested  by  eating 
rats  which  \ery  commonly  harbor  trichina  or  the  carcasses 
or  offal  of  swine  from  the  slaughter-house.  In  a  few  isolated 
instances  horses  have  been  infected  through  rats.  Mice  can 
also  be  the  host  of  trichina.  In  the  life-cycle  of  this  ])arasite 
four  stages  of  development  are  recognized: 

(a)  The  larva'  which  develop  in  the  intestine  into  sexually 
mature  males  and  females.  One  week  after  infestation  the 
females  bear  living  embryos. 

(//)  "^riie  embryos  wander  into  the  niiiscles,  passing  through 
the  chyle  vessels  into  the  thoracic  (hict  and  from  there  through 
the  bloodvessels  to  the  muscles. 


HOG  MEASLES— CYSTICERCUS  CELLULOSE        197 

(c)  The  embryos  in  about  one  month  become  encapsuled, 
which  process  lasts  about  three  months. 

(d)  A  cak'ification  of  the  encapsuled  trichina  begins  in 
from  three  to  six  months  and  lasts  about  eighteen  months. 
Encapsuled  trichina  can  live  for  years  in  the  muscle.  They 
produce  infestation  when  ingested;  unencapsuled  trichina 
are  killed  in  the  stomach.  The  favorite  seats  of  trichina  are 
the  muscular  portion  of  the  diaphragm,  the  larynx  and 
tongue,  abdominal  and  intercostal  muscles. 

Symptoms. — Symptoms  of  trichinosis  in  swine  from  natural 
infestation  have  not  been  observed.  From  artificial  infesta- 
tion the  symptoms  resulting  are  diarrhea  and  colic  at  the  end 
of  the  first  week,  and  stiffness,  paralysis  of  the  limbs,  pruritus, 
difficult  mastication,  dysphagia,  dyspnea,  hoarseness,  and 
edematous  swellings  in  the  second  or  third  week.  Usually, 
however,  these  cases  fully  recover  in  from  four  to  six  weeks. 

Treatment. — Xo  treatment  is  of  any  avail  once  the  worms 
have  reached  the  muscles.  As  a  prevention  the  hog  yards 
should  be  kept  free  from  rats  and  mice. 

HOG  MEASLES.     CYSTICERCUS  CELLULOSE. 

Definition. — Cysticercus  cellulos8e  is  the  ju\enile  form  of  the 
tapeworm  Tsenia  solium  of  man.  Young  swine  are  infected 
by  eating  the  proglottides  gathered  from  human  feces.  The 
eggs  are  digested  in  the  stomach  and  the  six  hooked  embryos 
are  set  free  after  which  they  pass  through  the  bowel  wall  and 
via  blood  reach  the  muscles  where  after  three  months  they 
form  cysts.  The  favorite  seats  of  the  cysts  are  in  the  abdom- 
inal muscles,  diapliragm  and  tongue.  The  cysts  are  pea-  to 
bean-sized,  dull  white  in  color,  each  having  an  inverted  head 
provided  with  four  suckers  and  a  double  row  of  hooks. 
]\leasles  is  a  rare  disease  among  American  swine. 

Symptoms. — During  life  symptoms  are  rarely  observed, 
although  in  isolated  instances  severe  brain  disturbance, 
blindness,  paralysis  of  the  tongue,  pleuritis  and  peritonitis 
have  been  noted.  If  the  tongue  is  involved  the  cysts  may  be 
seen  on  its  ventral  surface. 


198     DISEASES  OF  THE  ORGANS  OF  LOCOMOTION 

CYSTICERCUS  INERMIS. 

Definition. — ("ysticercus  iiierinis  is  tlio  juvenile  form  of  the 
Tsenia  saginata  of  man.  Cattle  become  infested  by  ingesting 
the  ])rogl()ttides  of  the  tapeworm  found  in  human  feces.  The 
favorite  seat  of  tlie  cyst  is  in  the  masseter  nniscles.  These 
l)arasites  cause  no  symptoms  in  cattle. 

MIESCHER'S  TUBULES. 

Definition. — These  are  sarcosporidia  (protozoa)  that  appear 
in  colonies  surrounded  by  a  sack-like  membrane.  They  occur 
in  the  striated  muscles,  forming  elongated  sacs  which  contain 
a  number  of  kidney-  or  bean-shaped  bodies  (sporozoites). 
The  favorite  seats  are  the  mouth,  throat  and  esophagus. 
They  produce  no  clinical  symptoms.  In  rare  instances  the 
sac  surrounding  them  may  rupture  and  lead  to  an  invasion 
of  the  muscles,  producing  a  myositis.  This  occurs  usually  in 
the  tongue;  or  they  may  induce  neoformations  in  the  lumbar 
muscles. 


PART  YIII. 
DISEASES  OF  THE  KIDNEYS. 


INFLAMMATION  OF  THE  KIDNEYS.     NEPHRITIS. 

While  from  a  pathological  standpoint  a  great  many  differ- 
ent varieties  of  nephritis  may  be  distinguished,  from  the 
clinical  side  foiu*  forms  are  recognized  in  animals: 

(a)  Acute  parenchymatous  nephritis. 

(b)  Chronic  interstitial  nephritis. 
((■)  Purulent  neplu-itis. 

id)  Pyelonephritis. 

Acute  Parenchjnmatous  Nephritis. — Definition. — An  inflam- 
mation of  the  functional  tissue  of  the  kidneys. 

Occurrence. — This  form  of  neplu-itis  is  the  most  common  in 
animals.  It  may  be  primary  and  due  to  the  action  of  toxic 
substances  or  perhaps  cold  on  the  kidneys,  or  secondary  to 
mfectious  diseases. 

Etiology. — Irritants,  such  as  cantharides,  mustard,  col- 
chicum,  carbolic  acid,  gasoline,  mercury,  cottonseed  meal, 
fungi,  free  hemoglobin,  etc.,  are  the  commonest  causes  of 
primary  neplu-itis.  Cold  is  probably  also  a  cause  or  at  least 
a  refrigeration  of  the  body  can  predispose  an  animal  to  neph- 
ritis. ]\Iost  cases  of  neplu-itis  in  animals,  however,  are  second- 
ary to  such  infectious  diseases  as  influenza,  hog  cholera, 
glanders  or  tuberculosis.  It  frequently  complicates  a^oturia, 
probably  due  to  the  action  of  the  free  hemoglobin  on  the 
kidney.  Xeplu-itis  may  further  be  due  to  an  inflammation  of 
the  renal  pelvis  or  urinary  bladder  (pyelitis,  cystitis).  In 
rare  instances  nephritis  may  be  caused  by  traumatism  or  still 
more  rarelv  attends  rheumatism.    Dift'use  skin  diseases  such 


200  DISEASES  OF  THE  r<:iDNEYS 

as  eczema  and  mange  maj'  cause  nephritis.  Obstriicti\e 
icterus  may  also  be  a  cause. 

Symptoms. — The  princi])al  sym])tom  of  acute  })arenchyma- 
tous  nephritis,  is  albiuniuuria.  Tlie  albimiin  content  ma\' 
reach  several  per  cent.  Fsually  the  quantity  of  urine  \()i(le(l 
is  greatly  diminished  (oliguria),  the  s})e('ific  gravity  high, 
color  dark,  and,  as  a  rule,  it  is  rich  in  sediment.  An  examina- 
tion of  the  urine  uncler  the  microscope  shows  it  to  contain 
tube  casts,  renal  epithelium,  white  or  red  corpuscles  and  in 
some  cases  blood  (hematuria).  Later  symptoms  of  dropsy 
api)ear,  such  as  edema  of  the  ventral  portion  of  the  abdomen, 
scrotum,  and  legs.  In  some  instances  the  patient  will  a})pear 
stiff,  stand  with  its  legs  spread  a])art,  or,  on  the  other  hand, 
drawn  U])  under  the  body  and  the  back  is  held  arched.  Pali)a- 
tion  of  the  kidneys  through  the  rectum  (small  horses)  causes 
the  animal  to  e\ince  pain.  Pressure  ()\er  the  kidneys  from 
the  outside  rarely  produces  symptoms.  The  general  condition 
of  the  patient  is  disturbed  in  that  it  seems  stu])id,  weak,  has 
no  ap])etite  and  shows  increase  in  tem])erature.  In  some  cases 
the  urine  is  voided  fre(|uently  in  small  (juantities,  often  only 
a  few  dro])s  dribbling  away  with  considerable  straining 
(stranguria).  These  symi)toms  are  most  commonly  seen  in 
diffuse  ne])hritis  the  result  of  ])()isoning  with  gasoline,  turj)en- 
tine,  or  cantharides.  In  stallions  there  may  be  a  ])artial 
erection  of  the  i)enis  (pria]:)ism)  from  the  urethral  irritation. 
In  some  instances  there  is  a  total  su])])ression  of  urine 
for  as  long  as  a  week  (aniu'ia).  In  fatal  cases  toward 
the  end  syni])t<)nis  of  uremia  appear  which  are  recog- 
nized by  convulsions,  coma,  and  usually  subnormal  tem- 
])erature. 

Diagnosis. — A  diagnosis  can  be  made  i)()sitively  only  by  a 
cliemical  and  microsco])ic  examination  of  the  urine  for  al- 
bumin, the  ])resence  of  tube  casts,  renal  e])ithelium,  red  and 
white  corpuscles,  and  even  blood. 

Course. — Cases  of  nei)hritis  secondary  to  infectious  dis- 
eases usuall\'  disap])ear  with  the  recovery  of  the  infectious 
disease,  healing  occurring  in  about  fourteen  days.  Cases 
which  end  fatally,  as  noted,  terminate  under  symptoms  of 
uremia. 


IXFLAMMATIOX  OF   THE  KIDXEYS—XEPHRITIS     201 

Prognosis. — The  prognosis  is  always  doubtful.  While  ap- 
parently severe  cases  do  reco\-er,  milder  ones  often  grow 
worse  and  lead  to  death.  When  oliguria  or  complete  anuria 
persists  and  the  chemical  and  microscopic  findings  continue  to 
show  evidenceof  further  kidney  destructionthe  prognosis  is  bad. 

Treatment. — Care  should  be  given  to  regidate  the  diet, 
avoiding  feeding  acrid  and  irritant  substances.  Herbivorous 
animals  should  be  allowed  grass,  hay,  and  roots  rather  than 
intensive  foods  like  grain.  When  available  milk  forms  a  good 
article  of  food.  Plenty  of  water  should  be  supplied  the 
patient,  as  it  tends  to  flush  out  the  obstructed  tubules. 
Linseed  tea  is  recommended  for  its  soothing  eflfect.  The  indi- 
cations are  to  relieve  the  kidneys  as  much  as  possible  by  util- 
izing the  skin  and  bowels  to  rid  the  body  of  waste  products. 
Among  the  drugs  diuretics  are  indicated,  such  as  acetate 
of  potash  (5ij-iv)  or  potassium  nitrate  (5ij-i^')-  I^ia- 
phoretics  also  assist,  such  as  pilocarpin  (gr.  iij-vj).  Keep- 
ing the  patient  in  a  warm  place,  hot  baths,  or  blankets  assist 
in  producing  sweat.  To  further  relie^■e  the  kidneys  laxatives 
should  be  given.  When  the  patient  shows  symptoms  of 
lu-emia  narcotics  such  as  morphin  (gr.  iij-v)  or  bromids 
are  useful. 

Chronic  Interstitial  Nephritis. — Definition. — A  form  of  in- 
flammation of  the  kidneys  which  attacks  princi])ally  the  inter- 
stitial connective  tissue.  The  chronic  fibrous  inflammation 
leads  to  a  contraction  and  hardenmg  of  the  kidney,  the 
surface  of  which  becomes  rough,  imeven,  covered  with  numer- 
ous projections  and  depressions,  leading  to  what  is  known  as 
granular  kidney.  Within  the  kidney  are  numerous  centres  of 
connective  tissue.  The  cortex  is  contracted,  causing  the 
tubular  portions  to  be  drawn  nearer  the  surface  of  the  organ. 
This  is  called  sclerotic  kidney  (nephritis  fibrosa  multiple). 
When  the  sclerosis  is  dift'use  the  organ  is  greatly  increased  in 
size,  is  of  semicartilaginous  consistency  and  of  white  color 
(nephritis  fibrosa  diffusa) . 

Occurrence. — Chronic  interstitial  nephritis  is  less  common 
in  animals  than  in  man.  It  does  occm,  however,  in  horses  and 
occasionally  in  cattle.  In  swine  it  is  rare,  as  these  animals 
are  iisualh-  killed  when  young. 


202  DISEASES  OF  THE  KIDNEYS 

Etiology.— This  form  of  nephritis  usually  develops  from  the 
acute  i)arenchymatous,  the  causes  of  which  huxe  i)een  given. 
In  the  horse  it  may  have  an  embolic  origin  emanating  from 
the  worm  aneurysm  in  the  anterior  mesenteric  trunk.  In 
cattle  it  sometimes  results  from  jjyelitis.  In  man,  sclerosis  of 
the  arteries  is  a  common  cause. 

Symptoms. — The  principal  symptom  of  clu-onic  interstitial 
neplu'itis,  contrary  to  the  acute  and  chronic  parenchymatous 
nephritis,  is  an  increase  in  the  quantity  of  urine  voided  by  the 
patient  (])olyuria).  The  urine  is  of  low  specific  gravity 
(1001  to  1010)  and  contains  little  albumin,  few  tube  casts, 
and  renal  epitheliimi.  Generally  associated  with  the  polyuria 
are  symptoms  of  hypertrophy  of  the  heart  (see  this),  which  is 
later  followed  by  dilatation  of  the  organ,  leading  to  sympt£)ms 
of  dropsy,  such  as  anasarca,  hydrothorax,  hydropericardium, 
and  ascites.  In  some  cases  uremia  may  follow  with  con\ul- 
sions  and  coma.  In  rare  instances  blindness  results  from 
albuminuria  retinitis. 

Prognosis. — The  prognosis  is  bad,  as  the  condition  is  gener- 
ally incurable.  As  the  efficiency  of  the  patient  (horses)  falls 
below  the  cost  of  keeping  many  of  them  are  destroyed  or 
traded  off. 

Treatment. — While  in  man  a  palliative  treatment  which  will 
jn-olong  life  is  indicated  (nitroglycerin,  digitalis,  strychnin) 
in  animals  this  does  not  pay.  Otherwise  the  treatment  is 
the  same  as  for  acute  parenchymatous  nephritis. 

Purulent  Nephritis.  —Definition.^ — A  suppurative  inflamma- 
tion of  the  kidneys  leading  to  diffuse  pus  infiltration  or  to 
abscess  formation  in  the  organ. 

Occurrence.^ — This  form  of  nephritis  is  usually  secondary  to 
sucli  diseases  as  strangles,  pyemia,  wound  infections,  etc. 

Etiology. — The  causes  are  pus-producing  bacteria  which  are 
carried  to  the  kidney  either  through  the  blood  or  come  from 
the  bladder  or  pelvis  of  the  kidney  through  the  urine.  Speci- 
fically staphylococci  and  streptococci  are  the  principal  causes. 
These  bacteria  produce  in  the  organ  either  a  disseminated 
purulent  nephritis  in  the  form  of  large  numbers  of  small 
abscesses,  foimd  principally  in  the  cortex  (nephritis  punctata), 
or  a  few  isolated  large  abscesses  (pyonephrosis).    In  cattle 


INFLAMMATION  OF  THE  KIDNEYS— NEPHRITIS     203 

this  form  of  nephritis  is  most  commonly  a  sequela  to  puerperal 
septicemia  and  in  the  horse  to  strangles,  pyemia  and  more 
rareh^  ])uri)ura. 

Symptoms. — The  symptoms  of  difi'nse  purulent  nephritis 
are  usually  so  vague  that  a  diagnosis  cannot  be  made  during 
life.  Where  symptoms  occur  that  are  at  all  characteristic 
both  kidneys  are  involved.  The  symptoms  are  very  like 
those  of  acute  parenchymatous  nephritis  (in  the  horse  colic 
attacks,  arching  and  rigidity  of  the  back,  shortening  of  the 
stride  in  one  or  both  hind  limbs,  etc.).  Cases  are  recorded 
where  the  enlarged  kidney  produced  swelling  in  the  lumbar 
region.  On  microscopic  examination  pus  cells  may  be  found. 
Albuminuria  is  also  present. 

Prognosis. — The  prognosis  is  grave,  as  sooner  or  later,  if 
both  kidneys  are  involved,  death  ensues  (uremia). 

Treatment. — ^Medicinal  treatment  in  animals  is  of  no  value 
as  far  as  producing  healing  is  concerned.  In  man  the  removal 
of  the  kidney  (nephrectomy)  is  practised. 

Pyelonephritis. — Definition. — Pyelitis  is  an  inflammation  of 
the  pelvis  of  the  kidney.  Pyelonephritis  is  a  combination  of 
pyelitis  and  nephritis. 

Occurrence. — In  Europe  pyelonephritis  is  common  in  cattle 
(cows).  A  few  cases  have  been  recorded  in  swine.  Statistics 
for  this  country  in  regard  to  the  prevalency  of  the  disease  are 
wanting. 

Etiology. — Pyelonephritis  may  develop  in  one  of  two  ways: 
(n)  As  a  bacterial  disease  which  is  the  most  common  form  in 
cattle,  or  (b)  it  may  be  caused  by  stones  or  concrements  which 
form  in  the  pelvis  of  the  kidney.  A  rare  cause  of  pyelo- 
nephritis is  the  giant  palisade-worm,  Eustrongylus  gigas. 

Bacterial  Pyelonephritis  of  Cattle. — As  noted  this  is 
the  most  common  inflammation  of  the  kidney  in  the  ox.  It  is 
probably  due  to  more  than  one  microorganism  (streptococci, 
colon  bacilli,  staphylococci),  but  the  corynebacillus  renalis  is 
the  chief  offender.  The  microorganisms  enter  the  kidney 
either  by  the  blood  or  the  urine.  The  bacteria  which  produce 
pyelonephritis  cause  a  variety  of  pathological  changes  in  the 
kidney.  As  a  rule  there  are  present  in  combination  dilatation 
of  the  pelvis  of  the  kidney,  which  is  usually  found  filled  with 


204  DISEASES  OF  THE  KIDNEYS 

pus  and  its  walls  ulcerated,  necrosis  of  tlic  papilla,  diffuse 
purulent  ne])liritis  with  abscesses  in  the  cortex  and  chronic 
interstitial  ne])hritis. 

Symptoms. — Most  cases  of  pyelonephritis  occur  in  cows  fol- 
lowing ])arturition.  This  is  es])ecially  true  when  injuries  have 
occurred  in  the  uterus  or  vagina  or  where  retention  of  the 
afterbirth  has  followed.  It  may,  however,  originate  independ- 
ent of  ])arturition.  In  sucklings  infection  through  the  navel 
can  occiu"  and  in  male  animals  it  has  resulted  from  primary 
abscesses.  There  is  also  a  probability  that  the  infection  may 
be  introduced  via  the  digestive  tract.  The  clinical  symptoms 
are  usually  rather  indefinite.  In  a  cow  which  has  calved  with 
difficulty  or  suffered  from  retention  of  the  ])lacenta  the  con- 
dition of  the  animal  grows  bad,  the  a])petite  and  rumination 
suppressed,  the  patient  losing  flesh,  showing  fever,  colicky 
pains,  irregular  gait,  frequent  urination  and  sometimes 
strangury.  Pressure  over  the  sacrum  causes  pain  and  the 
tail  and  buttocks  are  soiled  with  ])us  which  ffows  from  the 
vagina.  The  urine  in  rare  instances  remains  clear,  but  is 
usually  cloudy.  On  rectal  examination  the  bladder  is  found 
partially  filled,  the  ureters  dilated  and  sometimes  the  kidneys 
enlarged,  sensitive  and  fluctuating.  The  chemical  analysis  of 
the  urine  shows  albumin  and  free  annnonia.  Under  the 
microscope  jnis  cells,  blood,  crystals  of  trii)le  i)hospIiates, 
and  renal  epithelial  cells  are  found.  With  the  Gram  stain 
large  numbers  of  bacteria— the  corynebacilli — are  foimd 
generally  arranged  in  clumps.  As  cystitis  is  a  common  com- 
plication, bladder  c])ithclium  will  also  be  found  in  the  urine. 

Diagnusifi—  Diagnosis  depends  U])on  the  examination  of 
the  urine  and  the  determination  of  the  corynebacillus  which 
is  usually  ])resent. .  The  rectal  findings,  the  fact  that  the  urine 
contains  pus,  and  the  failing  of  the  ])atient  after  ])arturition, 
point  to  ])yel()ne])hritis  in  cows. 

Pto(7/?o.s'/.s'.— Prognosis  is  bad,  therefore  it  is  advisable  to 
make  the  diagnosis  as  early  as  possible  so  that  the  animal  may 
be  slaughtered. 

Calculous  Pyelonephritis  (Kidnri/  Stones). — Defini- 
tion.— This  is  an  inflanmiation  of  the  pelvis  of  the  kidney  due 
to  the  presence  of  renal  stones  (nephrolithiasis).    The  stones 


UREMIA  205 

consist  of  carbonate  of  lime,  oxalate  of  lime,  silicates  and  phos- 
phate salts.  Renal  stones  probably  develop  from  the  deposit 
of  salts  around  a  nucleus  such  as  mucous  epithelium  or  even 
bacteria.  They  induce  in  the  kidneys  various  changes  such 
as  pyelitis  or  pyelonephritis  and  the  so-called  hydronephrosis. 

Occurrence. — While  kidney  stones  are  rarer  in  animals  than 
in  man,  they  are  seen  occasionally  in  horses  and  cattle.  They 
also  occur  among  sheep  and  swine.  In  sheep  they  commonly 
result  from  the  feeding  of  root  crops,  such  as  potatoes,  sugar 
beets,  beets,  etc.  In  some  instances  among  sheep,  kidney 
stones  appear  enzootically. 

Symptoms. — The  s\Tiiptoms  are  rather  vague.  Very  often 
they  produce  no  symptoms  whatever.  In  other  cases  the 
patient  suffers  from  renal  colic,  bloody  urine,  partial  or  total 
suppression  of  mine,  and  even  uremia.  The  urine  passed  is 
sometimes  bloody  or  may  be  cloudy  from  pus.  Sometimes 
sand  or  grit  is  passed,  which  adlieres  to  the  hairs  around  the 
sheath  opening.  On  rectal  examination  the  symptoms  of 
pyeloneplu"itis  may  be  determined,  and  occasionally  a  slight 
crepitation  can  be  felt,  due  to  the  movement  of  the  stones 
against  one  another. 

Treatment. — The  treatment  in  animals  is  not  successful, 
and  operative  procedure,  except  in  dogs,  is  hardly  advisable 
on  account  of  the  risk. 

UREMIA. 

Definition. — A  poisoning  of  the  blood  with  the  constituents 
of  the  urine. 

Occurrence. — Uremia  can  occur  in  any  condition  in  which 
the  normal  discharge  of  lu-ine  is  impeded. 

Etiology. — Uremia  may  result  from  nephritis,  kidney 
tumors,  kidney  stones,  obstruction  of  the  ureters,  bladder, 
or  urethra,  or  paralysis  of  the  bladder. 

Symptoms. — The  symptoms  usually  follow  kidney  disease 
where  there  has  been  complete  retention  of  urine.  The 
jjatients  show  spasms,  weakness,  coma,  and  subnormal 
temperature.  The  respirations  are  generally  retarded,  and 
the  sweat  may  have  a  urinous  odor,  especially  after  rupture 


200  DISEASES  OF  THE  KIDNEYS 

of  the  bladder.  TJie  synii)t()ins,  as  a  rule,  occur  periodically, 
and  A'ery  often  lead  to  death,  which  may  follow  the  first 
convulsive  attack  or  after  repeated  attacks. 

Treatment. — I'nless  the  cause  of  the  retention  can  be  re- 
moved, treatment  is  useless.  The  remedies  achiscd  in  acute 
nej)hritis  fdiurctics,  (lia])horetics,  laxatives)  may  be  employed. 

CONGESTION  OF  THE  KIDNEYS   (HYPEREMIA). 

Definition. — Hyperemia  of  the  kidne\s  may  be  either 
arterial  or  venous.  Arterial  hyperemia  is  the  first  stage  of 
nephritis  (see  this).  It  is  caused  by  such  irritant  drugs  as 
cantharides,  turpentine,  or  gasoline;  acrid  j)lants,  mouldy 
food,  sea  water,  etc.,  can  also  produce  it.  Venous  congestion 
is  usually  due  to  organic  heart  disease  and  more  rarely  to 
pulmonary  emphysema. 

Symptoms. — The  j)rincii)al  symptom  of  arterial  congestion 
is  i)olyuria,  with  its  attending  increased  thirst.  Sometimes 
the  patient  shows  a  stiff  gait  and  sensitiveness  over  the  kid- 
neys. In  venous  congestion  due  to  the  fact  that  less  arterial 
blood  flows  through  the  kidneys,  oliguria  occurs.  Albimiin- 
uria  may  also  be  a  symptom,  due  to  the  fact  that  the 
nutrition  of  the  renal  epithelial  cells  suffers. 

Diagnosis. — Arterial  congestion  can  be  difTerentiated  from 
diabetes  insipidus  only  by  the  fact  that  it  is  temjxn-ary 
while  the  later  is  chronic.  Diabetes  mellitus,  on  account  of 
its  extreme  rarity  in  animals,  need  hardly  be  taken  into 
account.  Venous  hyperemia  is  differentiated  from  nephritis 
by  the  urine,  which  contains  very  little  albumin  and  no  cell 
elements.  The  patient  is  at  the  same  time  sulfcriiig  from 
some  chronic  heart  or  limg  disease. 

Treatment.— Arterial  congestion  disappears  as  soon  as  the 
causes  are  removed.  Otherwise  the  treatment  is  similar  to 
that  of  acute  nephritis.  A^enous  hyperemia  can  rarely  be 
removed,  as  a  basic  disease  is  usually  incurable. 

RENAL  HEMORRHAGE. 

Etiology. — Hemorrhage  from  the  kidneys  may  result  from 
traumatism  or  the  worm  aneurvs'm,  or  it  ma\'  be  embolic  in 


HYDRONEPHROSIS— CYSTIC  KIDNEY  207 

origin.     It  is  quite  often  fatal  in  horses,  especially  when 
traumatic. 

Symptoms. — The  symptoms  are  hematuria,  blood-tube  casts 
in  the  urine,  and  general  anemia. 

AMYLOID  KIDNEY. 

Amyloid  kidney  is  usually  associated  with  chronic  suppura- 
tive conditions  such  as  are  seen  in  strangles,  liver  abscesses, 
etc.    It  is  of  no  clinical  importance  in  veterinary  medicine. 

Symptoms. — The  symptoms  are  very  vague  (anemia, 
cachexia,  albuminuria  without  tube  casts). 

KIDNEY  TUMORS. 

The  kidneys  are  the  seat  of  several  kinds  of  tumors,  such 
as  sarcoma,  carcinoma,  adenoma,  melanoma,  etc.  They  can 
rarely  be  diagnosed  clinically.  Occasionally  they  may  be 
palpated  tlu-ough  the  rectum.  If  they  produce  symptoms 
they  are  hematuria,  uremia,  emaciation,  and  intermittent 
lameness  from  compression  and  tlirombosis  of  the  posterior 
aorta. 

Treatment. — Treatment  is  of  no  use  except  in  dogs,  where 
occasionally  nephrectomy  is  practised. 

HYDRONEPHROSIS.     CYSTIC  KIDNEY. 

Etiology. — This  condition  is  found  frequently  in  edible 
animals.  Cystic  kidney  is  usually  due  to  kidney  stones, 
especially  in  sheep,  where  SO  per  cent,  of  the  cases  are  due  to 
this  cause.  In  the  hog  it  is  said  to  result  from  a  congenital 
defect  in  the  opening  of  the  ureters,  which  are  placed  too 
low  at  their  point  of  entrance  into  the  bladder,  periodically 
preventing  the  urine  from  escaping. 

Symptoms. — Cystic  kidney  rarely  produces  symptoms  dur- 
ing life,  although  very  rarely  a  kidney  may  become  so  en- 
larged as  to  distend  the  abdomen  in  swine.  Occasionally  in 
horses  and  cattle  the  condition  may  be  palpated  per  rectum. 

Treatment. — Treatment  is  unavailing. 


208  DISEASES  OF  THE  KIDXEYS 

HEMATURIA. 

Definition. — By  hematuria  is  meant  1)1()0(1  in  the  urine. 
This  is  a  symptom  of  several  diseases  of  the  kichiey,  })la(l(ler, 
and  urethra.  It  is  also  associated  with  infectious  diseases 
(piiri)ura,.  anthrax),  poisoning  (turpentine,  gasoline)  and 
blood  diseases  (leukemia) . 

HEMOGLOBINURIA. 

Definition. — The  presence  of  hemoglobin  without  blootl  in 
the  urine.  It  is  a  symptom  of  several  different  diseases 
(azoturia,  Texas  fever,  etc.). 

PARASITES  IN  THE  KIDNEY. 

Eustrongylus  Gigas. — This  })arasite  is  rare  in  horses  and 
cattle.  It  is  a  large  worm  a])()ut  the  diameter  of  a  lead-pencil, 
varying  in  length,  depending  u])on  the  sex,  from  I'A  cm.  to  1  m., 
the  male  being  the  smaller.  It  is  not  known  how  the  worm 
enters  the  ])clvis  of  the  kidney.  It  produces  a  suppurative 
pyelonei)hritis,  and  eventually  total  destruction  of  the  kid- 
ney, which  is  transformed  into  a  thick-walled  sac  contain- 
ing pus  and  the  coiled  worm.  In  large  animals  the  symptoms 
are  very  vague,  as  usually  but  one  kidney  is  involved. 

A  <liagnosis  can  be  made  only  by  finding  the  brown-colored, 
oval  eggs,  showing  on  the  surface  numerous  round  depressions. 
The  worm  may  occasionally  pass  through  the  ureters  to  the 
bladder,  where  it  produces  cystitis.  Treatment  is  not  satis- 
factory in  large  animals. 

Other  Parasites  in  the  Kidneys. The  lar\<e  of  the  scleros- 
tomum  are  found  in  the  kidneys  of  the  horse,  where  they  give 
rise  to  hemorrhage  from  the  renal  arteries.  In  swine  the 
Stephanurus  dentatum  is  not  uncommon  in  the  fat  (leaf  lard) 
surrounding  the  ki(lne\-,  and  more  rarely  in  the  kidney  itself. 
It  is  usually  found  on  shiughter.  Cysticercus  cellulosjc  has 
been  found  in  the  kidney  of  pigs;  Echinococcus  polymorphous 
in  the  kidney  of  sheep. 


PART   IX. 
DISEASES  OF  THE  NERVOUS  SYSTEM. 


CHAPTER  I. 
DISEASES  OF  THE  BRAIN. 

Two  groups  of  symptoms  characterize  brain  and  meningeal 
lesions,  viz.:  (A)  General,  and  (5)  focal  or  topical  symptoms. 
The  general  s\Tnptoms  result  from  a  diffuse  disorder  of  the 
bram  cortex  with  increased  intracranial  pressure,  or  they 
may  arise  from  mcreased  mtracranial  pressure  alone.  The 
focal  s\Tnptoms  result  from  lesions  which  involve  well- 
defined'  fields,  centres,  or  tracts  of  the  brain,  the  functions 
of  which  are  interfered  with.  Both  groups  of  symptoms  can 
occur  simultaneously  or  each  independently  of  the  other. 

(A)  General  brain  symptoms.  These  consist  m:  (1)  Dis- 
turbed consciousness.  This  is  manifested  by  stupor,  dulness, 
sleepiness,  sopor,  or  even  coma;  vertigo  and  syncope  may 
occur.  On  the  other  hand,  there  may  be  excitement,  rest- 
lessness, maniacal  or  rabiform  manifestations.  (2)  Disturb- 
ance in  respirations.  The  respirations  are  affected  in  fre- 
quency and  rhythm,  producing  in  some  instances  a  change 
in  the  mode  of  breathing  (Che\Tie-Stokes,  Biot  respirations, 
etc.).  (3)  Disturbance  hi  the  manner  of  prehension  and 
mastication  of  food.  The  appetite  may  be  unpahed,  lost, 
or  vitiated,  and  food  and  water  are  taken  in  an  unphysio- 
logical  manner.  (4)  Abnormal  muscular  movements.  These 
may  be  expressed  in  general  tonoclonic  spasms  (epileptoid) , 
forced  movements,  or  there  may  be  paralysis  (general,  hemi- 
14 


210  DISEASES  OF  THE  BRAIN 

plegia,  etc.).  (5)  Changes  in  the  pulse,  ^^ariations  in  tlie 
frequency  and  rhythm  of  the  jnilse  are  obserxed.  Quite 
often  the  pulse  is  slow,  due  to  the  effect  of  increased  intra- 
cranial pressure  upon  the  vagus.  If  excitement,  fever,  or 
heart  weakness  be  j^resent,  however,  the  pulse  will  be  fast 
and  irregular.  ]Marked  variations  in  the  frequency  and 
rhythm  of  the  pulse  are  noted  in  acute  meningitis.  (G)  Eye 
symptoms.  These  are  manifested  by  contraction  or,  on  the 
other  hand,  marked  dilatation  of  the  pupils.  One  pupil  may 
be  dilated,  its  fellow  contracted.  Rolling  of  the  eyeballs 
(nj'stagmus)  and  amaurosis  are  not  unrarely  observed.  (7) 
Tendon,  skin,  and  pupil  reflexes.  The  tendon  reflexes  may 
be  increased,  especially  in  chronic  brain  diseases,  if  the 
inhibitory  action  of  the  cortex  is  out  of  function.  The 
reflexes  may  be  reduced  in  some  acute  brain  diseases  where 
the  inhibitory  function  of  the  cortex  becomes  on  the  contrary 
increased.  Where  coma  is  present  both  the  skin  reflex  and 
pupil  reactions  become  nil  and  the  tendon  reflex  (patellar, 
Achilles)  reduced  to  a  minimum. 

(B)  Topical  or  focal  symptoms.  The  knowledge  of  topical 
symptoms  in  anhnals  is  very  limited.  liOcalized  nervous 
diseases  in  animals  are,  however,  much  rarer  than  in  man. 
Topical  symptoms  produce,  generally  speaking,  sensory  or 
motor  disturbances. 

The  sensory  disturbance  consists  in  (a)  decreased  sensi- 
bility or  hypesthesia ;  (6)  absence  of  sensibility  or  anesthesia ; 
(c)  increased  sensibility  or  hyperesthesia. 

The  motor  disturbance  induces  (a)  s])asms  which  may  be 
clonic  or  tonic;  (6)  involuntary  (forced  or  unphysiological) 
movements;  (c)  disturbance  of  the  muscular  sense,  causing 
loss  of  coordination,  unphysiological  attitudes,  and  irregulari- 
ties in  gait,  or  paralysis,  which  may  be  comjilete  or  partial 
(paresis),  unilateral  (hemiplegia),  bilateral  (])araplegia),  or 
in  a  single  organ  or  part  (monoplegia).  Hemiplegia  has  its 
origin  in  the  brain,  paraplegia  in  the  spinal  cord,  and  mono- 
plegia may  have  a  central  (brain)  origin,  or  may  be  due  to 
disorder  of  i)eripheral  nerves. 


ANEMIA  OF  THE  BRAIN  AND  ITS  MEMBRANES     211 

ANEMIA  OF  THE  BRAIN  AND  ITS  MEMBRANES. 

Etiology. — Where  the  body  has  suffered  a  sudden  loss  of  a 
quantity  of  blood,  or  where  a  rush  of  blood  from  the  brain  to 
other  organs  occurs,  an  acute  anemia  of  the  brain  results. 
Examples  of  the  latter  instance  are  furnished  when  large 
amounts  of  exudate  or  transudate  are  removed  too  rapidly 
from  a  body  cavity  (hydrothorax,  ascites)  or  large  amounts 
of  gas  from  the  bowels.  Acute  heart  weakness  or  a  general 
dilatation  of  the  bloodvessels  as  is  sometimes  associated 
with  severe  infections  and  many  poisonings  will  also  produce 
acute  anemia. 

A  chronic  anemia  of  the  brain  accompanies  general  anemia, 
specific  diseases  of  the  blood  (leukemia),  increased  intra- 
cranial pressure,  and  very  rarely  results  from  compression  or 
thrombosis  of  the  carotids. 

Symptoms. — Acute  anemia  of  the  brain  produces  dis- 
turbance in  consciousness.  The  animal  walks  with  a  stagger- 
ing gait,  the  patient  finally  falling  to  the  ground  as  if  lifeless. 
Vomiting  animals  may  vomit.  The  mucous  membranes  are 
very  pale,  the  pupils  dilated,  the  pulse  rapid  and  tlu-ead-like, 
the  respirations  either  slow  and  deep  or  accelerated  and  super- 
ficial. In  severe  cases  the  syncope  may  be  interrupted  by 
convulsions  and  the  death  of  the  patient.  In  milder  cases 
the  animal  returns  gradually  to  consciousness,  remains  for 
a  time  stupid  and  languid,  and  with  a  tendency  to  re- 
lapses. 

Chronic  brain  anemia  usually  produces  no  symptoms,  as 
the  condition  develops  gradually,  the  brain  adapting  itself 
to  it. 

Prognosis. — The  prognosis  varies  with  the  cause.  In  acute 
cases  as  long  as  the  pupil  reacts  to  light  recovery  is  probable. 
On  the  other  hand,  if  there  is  no  reaction,  and  especially  if  the 
patient  shows  svmptoms  of  convulsions,  the  prognosis  is 
bad. 

Treatment. — Stimulating  agents  are  recommended,  such  as 
rubbing  the  surface  of  the  body;  allowing  the  patient  to 
inhale  fumes  of  ammonia;  subcutaneous  injections  of  ether, 
caffein,  or  oil  of  camphor;  internally  alcohol  or  black  coffee 


212  DISEASES  OF  THE  BRAIN 

arc  indicated.  In  small  animals  the  electric  l)attery  may  he 
useful.  In  chronic  cases  only  a  successful  treatment  of  the 
basic  disease  will  heal  the  brain  anemia. 


CONGESTION    OF   THE    BRAIN    AND   ITS   MEMBRANES. 

Brain  congestion  may  be  acti\e,  due  to  an  engorgement  of 
the  brain  with  aterial  })lood,  or  it  may  be  passive,  caused 
by  a  stoppage  of  the  outflow  of  venous  blood. 

Etiology.— Passive  congestion  rarely  produces  symptoms  in 
animals.  An  active  hyperemia  of  the  brain  can  be  caused 
by  an  increased  heart  activity  and  the  loss  of  tonus  in  the 
cerebral  arteries  due  to  overwork,  rough  treatment  of  young 
animals  (breaking  colts;  the  excitement  of  railway  or  ship 
transportation);  estrum;  fright;  hypertroj)hy  of  the  heart; 
acute  alcohol  poisoning;  sun-  and  heatstroke.  A  collateral 
congestion  may  result  from  compression  of  the  large  blood- 
vessels of  the  abdomen  in  severe  bloating  of  the  stomach  or 
bowels.  An  active  hyperemia  of  the  brain  is  the  first  stage 
of  inflammation. 

A  passive  hyperemia  occasionally  occurs  from  compression 
of  the  jugulars  from  ill-fitting  collars,  too  tight  throat  latches 
("choking  down"  of  horses),  tumors,  inflammatory  swellings 
or  enlarged  th\Toids  which  press  upon  the  jugulars.  It  may 
also  be  a  symptom  of  heart  weakness,  chronic  diseases  of 
the  lung,  or  compression  of  the  lung  from  gas  accumulation 
in  the  stomach  or  bowels. 

Symptoms. — The  symptoms  of  active  hyperemia  are  those 
of  excitement,  which  usually  is  soon  followed  by  a  stage  of 
depression.  The  pui)ils  are  dilated,  the  nnicous  membrane  of 
the  head  congested,  the  pulse  and  respirations  are  increased 
in  frequency,  and  the  poll  feels  warm.  Very  probably,  how- 
ever, these  symptoms  represent  a  transient  inflammation  of 
the  brain,  often  the  result  of  a  chronic  hydr()cc])halus,  whicii 
occasionally  "flares  uj)"  in  this  form. 

A  severe  passive  hyperemia  causes  the  animal  to  show 
stu]ior,  sopor,  the  mucous  membranes  cyanotic,  the  pulse 
small  and  rapid,  and  the  patient  dyspneic. 


SUN-  AND  HEATSTROKE  213 

Course. — In  primary  active  hyperemia  the  symptoms  disap- 
pear suddenly  in  a  few  hours,  or  the>'  may  subside  gradually. 
In  the  passive  form  the  symptoms  disappear  as  soon  as  the 
causes  are  removed.  Where  this  is  impossible  the  patient 
will  be  subject  to  repeated  attacks,  and  eventually  the  con- 
dition may  lead  to  the  animal  becoming  a  "dummy." 

Diagnosis. — The  diagnosis  largely  depends  upon  the  short 
duration  of  the  symptoms.  Obviously  we  should  take  into 
consideration  the  species,  age,  and  condition  of  the  patient. 
There  are  many  conditions  which  simulate  and  are  probably 
accompanied  by  cerebral  congestion  (nymphomania,  infec- 
tious diseases,  gastro-intestinal  troubles,  especially  forage 
poisoning) . 

Treatment. — The  patient  should  be  kept  in  a  cool,  quiet 
place  and  fed  easily  digested  food.  Bleeding  from  the  jugular 
and  cold  applications  to  the  poll  are  recommended.  Internally 
a  good  purge  should  be  given.  Passive  h^^eremia  due  to 
ill-fitting  collars  demands  a  change  in  the  harness.  Cases  of 
heart  weakness  should  be  treated. 

SUN-  AND  HEATSTROKE. 

Sunstroke. — Sunstroke  is  a  disorder  of  the  brain  and 
spinal  cord  produced  by  exposure  to  the  direct  rays  of  a  hot 
sun  acting  upon  the  head.  From  a  pathological  standpoint 
it  may  be,  depending  on  the  degree,  a  congestion,  hemorrhage, 
inflammation,  or  paralysis  of  the  brain.  Therefore  the 
patient  will  show  varied  symptoms,  such  as  excitement, 
raging,  spasms,  or  death  may  occur  suddenly  from  apoplexy 
or  respiratory  arrest. 

Treatment. — ^Treatment  consists  in  the  application  of  cold 
to  the  head  and  the  use  of  caffein,  camphor,  or  veratrin.  To 
relieve  the  bowels  arecalin  or  eserin  may  be  used. 

Heatstroke. — Heatstroke  is  produced  by  prolonged  expo- 
sure to  high  temperatiu'es,  especially  during  exercise.  It  is 
seen  most  commonly  in  swine  that  are  being  driven  or  horses 
overworked  in  hot  weather. 

Symptoms. — The  symptoms  are  those  of  heart  weakness 
(palpitation,  rapid,  weak  pulse,  dyspnea  and  cyanosis).    The 


214  DISEASES  OF  THE  BRAIN 

patient  is  usually  very  languid,  the  gait  staggering,  and  there 
is  a  profuse  outbreak  of  sweat.  Tenijjeratiu'e  may  reach 
110°  F.  or  over. 

Prognosis. — The  i)rognosis  is  bad,  the  animal  usually  dying 
of  asphyxia. 

Treatment. — Heatstroke  is  treated  much  the  same  as  sun- 
stroke. Atropin,  caffein,  and  camphor  are  used  with  cold 
applications  (hosing)  to  the  body.  To  relieve  the  dysjjnea 
due  to  edema  of  the  lungs,  bleeding  may  be  resorted  to.  The 
temperature  may  be  reduced  by  cold  enemas. 

TRAUMATIC  INJURY  AND  CONCUSSION  OF  THE  BRAIN. 

Definition. — A  bruising  of  the  brain  the  result  of  direct 
injury  to  the  cranium  or  other  part  of  the  head. 

Etiology. — In  horses  contusion  and  concussion  of  the  brain 
may  result  from  kicks,  blows,  collisions  during  runaways, 
falling  upon  the  head,  etc.  In  cattle  it  may  be  due  to  the 
animal  falling  heavily  or  being  horned  by  another.  The  result 
of  the  injury  is  very  varied.  In  some  instances  a  fracture  of 
the  skull  with  hemorrhage  results;  in  others  there  is  a  bruis- 
ing of  the  brain  substance  without  even  the  skin  showing 
lesion.  Undoubtedly  more  or  less  hemorrhage  occurs  in  the 
brain  substance  and  intracranial  tension  is  increased.  The 
patient  also  suffers  from  shock. 

Symptoms. — Following  violent  blows  on  the  head  the  symp- 
toms usually  ai)j)ear  at  once ;  in  some  cases,  however,  an  hour 
or  two  may  elapse  before  they  make  themselves  manifest. 
The  symptoms  are  generally  the  result  of  accumulations  of 
blood  in  the  brain,  due  to  the  traumatism.  Where  the  injury 
has  not  been  great  the  animal  a])i)cars  stunned,  falls  to  the 
ground,  where  it  may  remain  for  ten  to  twenty  minutes,  to 
finally  regain  complete  consciousness.  Sometimes  permanent 
symptoms  may  be  left  behind.  When  the  injury  has  been 
severe  the  animal  is  found  lying  unconscious,  ])ui)ils  dilateds 
and  reflexes  dormant.  The  res])ir;itions  are  slow  and  irregu- 
lar, the  pulse  usually  ra])id,  but  occasionally  slow  and  often 
arhythmic.  Incontinence  of  feces  and  urine  may  occur, 
Usuall}^  after  lying  unconscious  for  a  few  hours  the  reflexe, 


LIGHTNING  STROKE— ELECTRIC  STROKE         215 

react  to  stimuli;  twitching  of  muscles  appear  and  rolling  of 
the  eyeballs.  The  annual  finally  rises  to  its  feet,  and  provided 
no  injury  to  the  motor  tracts  has  resulted,  it  appears  normal. 
In  the  latter  case  it  may  be  left  paralyzed.  In  severe  cases 
the  patient  does  not  regain  consciousness  and  dies  under 
convulsions. 

With  the  return  of  consciousness  sometimes  the  animal  is 
left  paralyzed;  quite  commonly  the  paralysis  assumes  the 
form  of  a  hemiplegia.  However,  depending  upon  what  motor 
tracts  are  involved,  the  form  of  paralysis  will  vary. 

Diagnosis. — When  the  history  of  injury  is  clear  the  diag- 
nosis is  not  difficult.  On  the  other  hand,  if  there  is  no  such 
history  and  no  lesions  about  the  head  can  be  noted  a  contusion 
might  easily  be  confused  with  cerebral  hemorrhage  (apoplexy) 
or  inflammation  of  the  brain.  The  sudden  appearance  of 
severe  brain  symptoms  without  fever  is  significant  in  this  regard . 

Prognosis. — Contusion  of  the  brain  in  most  cases  leads 
directly  or  indirectly  to  the  death  of  the  patient.  Obviously 
mild  cases  when  the  animal  has  been  only  stunned  recover. 
]\Iany  patients  which  do  not  die  are  left  permanently  crippled 
through  resulting  paralysis. 

Treatment. — The  head  of  the  patient  should  be  elevated 
and  cold  applied  to  the  poll.  Excitants  such  as  ether  or 
camphor  may  be  used  internally.  After  return  to  conscious- 
ness the  use  of  deep  bedding  or  slings  may  be  recommendable, 
depending  upon  the  individual  case. 

LIGHTNING  STROKE.     ELECTRIC  STROKE. 

By  lightning  or  electric  stroke  we  understand  an  injury 
to  nerve  tissue  produced  by  powerful  currents  of  electricity. 
In  some  instances  no  pathological  change  is  found  in  the  tissue, 
the  condition  being  functional. 

Occurrence. — Lightning  stroke  commonly  occm'S  in  the 
open  country,  animals  on  pasture  being  victims.  In  the  city 
horses  occasionally  come  in  contact  with  high-tension  wires 
which  have  fallen  upon  the  street.  Diuing  the  summer  sea- 
son thousands  of  animals  are  killed  or  injured  annually  by 
lightning  on  the  farms  of  this  country. 


21G  DISEASES  OF  THE  BRAIN 

Symptoms. — I'siially  u  liglitning  stroke  kills  tlie  unimal 
either  instantly  or  in  a  few  minutes.  In  other  cases  the 
animal  ai)pears  stumied  from  the  stroke,  but  soon  regains 
consciousness  and  normal  condition.  In  a  few  instances, 
howe\er,  the  patient  is  left  for  a  time  with  irregular  gait, 
weakness  of  the  hind  parts,  may  show  forced  mo^•ements,  and 
appear  stupid  and  dull.  Usually  they  recover  after  a  few 
days  or  weeks.  In  rare  cases  topical  symptoms  are  retained, 
such  as  monoplegia,  paraplegia,  paralysis  of  individual 
ner\-es,  from  which  the  animal  usually  recovers  in  one  or  two 
months.    Horses  are  sometimes  left  permanently  blind. 

Occasionally  lightning  stroke  produces  peculiar  markings 
or  figures  on  the  hair  or  skin.  These  figures  are  often  branched 
and  forked,  and  may  in^•()l\•e  pigmented  as  well  as  unpig- 
mented  skin.  On  the  un])igmented  skin  they  are  dark  colored 
and  sometimes  resemble  a  tree  or  forked  shrub. 

Treatment. — If  the  patients  remain  down  good  bedding 
should  be  provided.  To  assist  the  return  to  consciousness 
excitants  (alcohol,  ether,  camphor,  cafiein,  skin  rubbing)  may 
be  tried.    Usually  treatment  is  unnecessary. 


HEMORRHAGE  IN   THE  BRAIN   AND  ITS   MEMBRANES. 
APOPLEXY. 

Definition. — By  a})0])lexy  in  a  narrow  sense  is  imderstood  a 
hemorrhage  of  the  brain  or  its  membranes  ^^'hich  is  due 
neither  to  traumatism  nor  inflammation. 

Etiology. — The  causes  are  yery  varied.  In  many  of  the 
acute  infectious  diseases  (anthrax,  purpura  hemorrhagica, 
hemorrhagic  septicemia),  blood  diseases  (anemia,  leukemia), 
and  in  chronic  inflanunation  of  the  liver  and  kidneys  the 
walls  of  the  bloodvessels  in  the  brain  become  weakened,  a 
condition  conducive  to  hemorrhage.  In  rarer  instances  para- 
sites (larva?  of  sclerostomes)  form  a  cause.  Arteriosclerosis, 
a  common  cause  of  apoplexy  in  man,  probably  does  not  occur 
in  animals. 

Symptoms. — If  the  hemorrhage  is  severe  enough,  general 
brain  symptoms  appear  with  which  are  associated  topical 


MENINGO-ENCEPHALITIS  217 

symptoms.  The  gait  becomes  ii-regiilar,  the  patient  may  show 
forced  movements,  and,  eventually,  will  fall  to  the  ground 
miconscious  and  die  in  convulsions.  In  other  cases  the  animal 
later  regains  consciousness  but  for  an  indefinite  period  shows 
topical  symptoms  which  may  later  lead  to  death. 

Diagnosis.— The  symptoms  are  obviously  very  similar  to 
those  noted  in  contusion  of  the  brain.  The  diagnosis  depends 
largely  upon  the  sudden  appearance  of  severe  disturbance  in 
consciousness  without  history  of  injury. 

Treatment.— During  the  stage  of  unconsciousness  the  treat- 
ment is  the  same  as  for  contusions  and  concussion  of  the 
brain.  The  topical  symptoms  (local  paralyses)  which  remain 
behind  may  be  treated  by  passi\^e  mo^'ements  of  the  par- 
alyzed extremities  and  the  use  of  the  electric  battery.  lodid 
of  potash  is  also  recommended. 


MENINGO-ENCEPHALITIS. 

Definition.— By  meningo-encephalitis  is  meant  an  inflamma- 
tion of  the  pia  mater  and  brain.  Throughout  the  brain  sub- 
stance occur  numerous  small  centres  of  cell  infiltration. 

Occurrence. — In  a  primary  form  the  disease  is  most  common 
in  horses.  It  is  rare  in  other  animals.  In  the  horse  it  is  most 
apt  to  occiu"  during  the  warm  season. 

Etiology.— The  disorder  may  be  primary  or  secondary. 
The  primary  cases  are  usually  the  result  of  infection.  Several 
organisms  ('micrococci,  diplococci)  have  been  accused.  Other 
infectious  agents  such  as  the  necrosis  bacillus  and  the  Micro- 
coccus ascoformans  have  been  determined  in  the  meningeal 

exudate.  .       ,      •  , 

In  cattle  the  disease  is  quite  commonly  associated  with 
parturition  occurring  as  a  puerperal  meningitis  manifesting 
itself  up  to  two  days  before  calving.  Certain  predisposing 
causes  which  reduce  the  resistance  of  the  patient  are  un- 
doubtedly factors.  Therefore  unfavorable  weather,  working 
the  horse  in  the  hot  sunshine,  intensive  feeding,  hot,  illy 
ventilated  stables,  overexertion,  tying  the  head  too  high 
after  operations,  etc. 


218  DISEASES  OF  THE  BRAIN 

A  secondary  mciiing()-eiifc])lialitis  may  follow  straiif^les  in 
the  horse  or  tiibercnlosis  in  the  ox.  Obviously,  meningo- 
encephalitis may  also  result  from  traumatism,  inflammation 
of  the  brain  and  meninges  following  an  injury.  Abscesses 
in  the  neighborhood  of  the  cranium  (eye  socket),  necrosis 
of  the  atlas,  diseases  of  the  middle  ear,  etc.,  may  lead  to  an 
infection  of  the  brain. 

In  rare  cases  parasites  (sclerostomes,  Gastrophilus  equi, 
coenurus  and  cysticerci)  may  be  causes. 

Symptoms.^ — The  symptoms  of  brain  disturbance  usually 
de\elop  rapidly.  The  patient  appears  stupid,  languid,  the 
facial  expression  staring,  and  the  attitude  unphysiological. 
Horses  often  stand  with  their  fore  and  hind  feet  drawn 
together,  the  head  pendent,  and  the  eyelids  partially  closed. 
The  patient  pays  little  or  no  attention  to  its  surroundings, 
does  not  eat,  and  fails  to  o})ey  commands.  The  gait  is  awk- 
ward, stumbling,  and  sometimes  the  fore  feet  are  lifted  as  if 
the  horse  were  wading  in  w^ater.  There  are  often  marked 
symptoms  of  cerebral  excitement,  the  patient  running  about 
in  an  aimless  fashion,  not  infrequently  colliding  with  the  fence, 
building,  or  whatever  may  come  in  its  way.  Forced  move- 
ments are  also  observed,  the  animal  walking  in  a  circle. 

Cattle  are  restless,  look  wild,  bellow,  tear  u])  the  earth  with 
their  horns,  an^  may  even  attack  persons.  They  finally  drop 
to  the  ground  and  are  seized  with  convulsions.  In  tubercular 
meningitis  symptoms  of  excitement  are  usually  absent. 

Following  the  stage  of  excitement  which  usually  lasts  not 
over  half  an  hour  the  patient  goes  over  into  a  stage  of  stui)or, 
seems  oblivious  of  its  surroundings,  stands  with  the  eyelids 
half-closed,  head  sunken,  chin  resting  upon  the  edge  of  the 
manger,  or  quite  commonly  the  head  is  forced  into  a  corner. 
The  gait  is  often  irregular,  awkwartl,  the  patient  stumbling 
and  falling  as  it  progresses. 

While  the  respirations  are  accelerated  in  the  stage  of 
excitement,  in  the  second  stage  they  are  usually  slower  than 
normal  and  deeper.  Sometimes  Cheyne-Stokes  respirations 
have  been  noted.    The  pulse  may  be  too  rapid  or  too  slow. 

During  the  stage  of  excitement  the  sensibility  of  the 
patient  is  increased;  later  greatly  reduced.    The  poll  of  the 


MENINGO-ENCEPHALITIS  219 

head  may  feel  warm;  striking  it  lightly  with  a  percussion 
hammer  causes  the  patient  to  wince.  The  papilla  of  the  eye 
is  intensely  congested. 

Topical  symptoms  in  meningo-encephalitis  are  rare  in 
animals.  They  consist  in  spasms  of  the  eye  muscles  (nystag- 
mus) or  a  deviation  of  one  of  the  eyes  from  its  proper  direction 
(strabismus) ;  the  pupil  may  be  fixed  or  react  slowly  to  light; 
quite  frequently  the  pupils  are  of  unequal  size ;  spasms  of  the 
masseter  muscles  causing  gnashing  of  the  teeth  or  even 
trismus;  the  muscles  of  the  lips,  nose,  ears  and  neck  may 
also  show  spasmodic  contractions.  Paralysis  of  peripheral 
parts  such  as  the  pharynx,  tongue  and  the  lids  occasionally 
occur.    Hemiplegia  is  a  rarer  consequence. 

Fever  is  usually  noted  in  the  beginning  of  the  disease. 
If  the  temperature  remains  high  during  the  latter  stages, 
it  is  probably  due  to  septic  infection  or  pneumonia  which  may 
complicate  the  disease. 

The  appetite  is  impaired  or  suppressed  and  the  prehension 
of  food  unphysiological,  the  animal  eating  and  drinking  much 
as  does  a  "dummy." 

Course. — The  disease  develops  in  two  or  three  days.  It 
may  develop  suddenly  with  symptoms  of  excitement  and 
violence  followed  by  those  of  mental  depression  and  stupor, 
the  animal  dying  in  less  than  a  day.  In  othei*  cases  the  de- 
velopment is  much  slower,  the  animal  showing  no  very  pro- 
nounced symptoms  but  seems  mentally  perturbed,  shows 
impaired  appetite,  expressionless  countenance,  labored  loco- 
motion, etc.,  symptoms  which  in  two  or  three  weeks  attain 
a  higher  degree.  Tubercular  meningitis  in  cattle  usually 
assumes  a  subacute  course  and  develops  slowly.  In  some 
cases  improvement  is  followed  by  a  relapse.  Meningo- 
encephalitis is  not  infrequently  complicated  by  pneumonia 
(hypostatic  or  foreign  body),  septicemia,  or  pyemia. 

Diagnosis. — The  diagnosis  depends  upon  the  history  of 
some  infection,  the  symptoms  of  rapidly  increasing  disturb- 
ance in  consciousness,  the  eye  symptoms  (pupils  of  unequal 
size,  strabismus,  nystagmus,  congestion  of  the  papilla), 
trismus,  and  sensitiveness  of  the  poll.  Where  these  symptoms 
are  vague  the  diagnosis  is  extremelv  difficult. 


220  DISEASES  OF  THE  BRAIN 

From  the  standpoint  of  differential  diagnosis  the  foUowinji; 
conditions  must  be  taken  into  consideration: 

(a)  Functional  disturhances  of  the  brain  such  as  accom- 
pany acute  feverish  infectious  diseases.  These  are  accom- 
panied by  mental  depression,  disturbance  in  consciousness, 
etc.  The  diagnosis  here  would  dei)end  ujx)!!  the  evidence  \)i 
the  existence  of  the  primary  disease,  and  the  fact  that  the 
brain  symptoms  are  not  as  well  devel()])e<l  as  in  meningo- 
encephalitis. 

Meningo-euce])halitis  might  be  confused  with  rabies.  In 
rabies,  however,  consciousness  is  not  disturbed  in  the  begin- 
ning, the  clinical  symptoms  develop  progressively  and  char- 
acteristically (melancholia,  frenzy,  ])aralysis),  and  forced 
movements  and  s])asms  fail.  Acute  encephalitis  could  only 
be  excluded  in  cases  where  topical  symptoms  appear  early 
(hemiplegia,  ataxia,  monoplegia,  etc.).  A  tubercular  menin- 
gitis could  only  be  diagnosed  by  discovering  a  tubercular 
iritis  (rare),  the  evidence  of  tuberculosis  in  other  organs 
and  the  tuberculin  test. 

(6)  Poisonings  (lead,  mercurj-,  brine,  santonin,  tobacco, 
poppy  leaves,  opium,  etc.)  also  produce  functional  brain 
disturbances  which  resemble  the  synij)toms  of  meningo- 
encephalitis. Tsually  the  history  coii])le(l  with  the  fact  tliat 
the  patients  show  at  the  same  time  gastro-intestinal  symp- 
toms suffice  for  the  diagnosis.  Brain  disturbance  is  also 
noted  in  some  cases  of  helminthiasis  and  in  forage  poisoning. 

Prognosis. — Excei)t  in  the  ]Micr])cral  form  in  cows,  which 
often  reacts  faAorably  to  ])ro])er  treatment  applied  early, 
meningo-encephalitis  is  a  very  fatal  disease.  The  mortality  is 
over  75  per  cent.  In  the  horse  those  cases  which  do  recover 
are  left  "dummies"  from  consequent  hydrocephalus.  Fur- 
thermore, amaurosis,  <leafness,  muscular  i)aralysis  frequently 
follow  in  the  wake  of  the  disease. 

Treatment.^ — The  treatment  consists  in  ])lacing  the  animal 
in  a  cool,  darkened,  well-ventilated  stall,  best  in  a  box  stall 
where  it  may  run  free,  using  short  straw  for  bedding  so  that 
its  feet  will  not  be  entangled.  The  food  should  be  easily 
digestible;  if  the  animal  cannot  eat,  rectal  feeding  may  be 
resorted  to.    To  the  poll  cold  applications  may  be  applied. 


ENCEPHALITIS— INFLAMMATION  OF    THE  BRAIN     221 

Internally,  provided  the  animal  can  swallow,  cooling  laxa- 
tives such  as  salts  should  be  given.  Pilocarpin  (3  to  6  grs. 
subcutaneously)  is  recommendable.  Arecalin  (1  or  2  grs. 
subcutaneously)  can  also  be  employed.  In  the  early  stages 
bleeding  has  been  tried  with  apparently  good  results. 

When  the  animal  is  very  restless  and  excited  clysters  of 
chloral  hydrate  may  be  used.  Convalescence  is  usually 
protracted. 


ENCEPHALITIS.     INFLAMMATION    OF    THE    BRAIN. 

Definition.^Encephalitis  is  an  inflammation  of  the  brain 
which  is  usually  circumscribed  and  confined  to  certain  well- 
defined  areas.  It  nearly  always  results  from  infection  and 
appears  either  as  a  suppurative  or  a  non-suppurative  process. 

Non-suppurative  Encephalitis. — Definition. — Non-suppura- 
tive encephalitis  is  an  inflammation  of  the  brain  tissue 
occurring  usually  in  the  form  of  multiple  foci  which  some- 
times are  hemorrhagic.  It  is  not  an  uncommon  sequela  to 
acute  infectious  diseases,  although  it  may  occur  independent 
of  these. 

Occurrence. — While  any  of  the  domestic  animals  are  sub- 
ject to  it,  it  is  most  frequent  in  the  horse  and  dog. 

Etiology. — Xon-suppmative  encephalitis  is  the  result  of  in- 
fection or  bacterial  intoxication.  In  the  first  instance  it  may 
be  secondary  to  specific  infectious  diseases  (infectious  pneu- 
monia of  the  horse,  strangles),  the  viruses  of  these  diseases 
circulating  through  the  brain,  or  it  may  be  secondary  to 
some  local  bacterial  infection,  the  toxins  of  which  reach  the 
brain. 

Cases  of  encephalitis  may  occur  concomitant  with  or 
follow  infectious  pneumonia  or  strangles  in  the  horse,  which 
in  some  outbreaks  of  these  diseases  occurs  more  commonly 
than  in  others.  In  rabies  encephalitis,  often  hemorrhagic,  is 
occasionally  well  developed. 

Encephalitis  may  also  result  from  sunstroke.  Feeding 
heavily  on  certain  foodstuffs  (legumes,  rye)  may  predispose 
the  animal. 


222  DISEASES  OF  THE  BRAJX 

Symptoms. — If  encephalitis  is  secondary  to  some  specific 
infectious  disease  the  sym])t()ms  of  it  may  be  masked  by  tlie 
basic  disorder.  As  a  rule  the  cerebral  symptoms  which  l)egin 
either  gradually  or  quite  ra])idly  (hemorrhage)  manifest 
themselves  as  disturbance  in  consciousness.  The  ])aticnt 
appears  languid,  stupid,  more  or  less  oblivious  of  its  surround- 
ings, and  assumes  unphysiological  postures.  The  gait  is 
staggering  or  the  patient  may  be  down  in  a  soporous  or  e\'en 
comatose  condition.  Sometimes  in  the  horse  the  patient  will 
show  symptoms  of  cerebral  excitement  or  even  rabiform 
symptoms.  These  are  usually  followed,  however,  within  a 
short  time  by  stupor.  The  patient  maj^  show  forced  movements. 

The  topical  symptoms  are  usually  not  determinable  if  there 
is  much  mental  depression.  However,  some  of  them  may 
be  notable,  such  as  paralysis  of  tlie  pharynx,  tongue,  larynx, 
eyelids,  dilated  pupils,  etc.  If  the  inflammation  of  the  brain 
is  diffuse  a  general  paresis  may  result,  the  patient  being 
unable  to  regain  its  feet  when  down  or  walk  without  sup])ort 
when  up.  If  the  respiratory  centre  becomes  involved  fatal 
dyspnea  may  result.  The  tem])erature  is  usually  ele\ated 
(105°  F.),  but  the  fever  is  mild  and  may  be  entirely  absent  in 
protracted  cases.  The  pulse  is  generally  in  harmony  with  the 
temperature.  Both  are  increased  during  the  stage  of  excite- 
ment. In  the  earliest  stages  the  ai)})etite  is  good,  provided 
the  basic  disease  present  has  not  already  interfered.  If  the 
mental  depression  is  marked,  however,  the  patient  may 
refuse  to  eat. 

Course.^ — The  usual  run  of  acute  encephalitis  is  two  to  fi\c 
days.  Subacute  cases  may  last  for  weeks  and  chronic  ones 
for  years,  producing  the  so-called  "dummy." 

When  the  development  is  rapid,  disturbance  in  conscious- 
ness soon  appears.  With  the  develoi)ment  of  the  nuMital 
symptoms  the  toj)ical  sNinptoms  usually  kec])  i)ace.  Re- 
covery occurs  exceptionally.  In  influenza  the  course  is  more 
favorable.  Cases  which  do  not  die  usually  lead  to  the  i)atient 
becoming  a  "dummy"  which  not  infrec|uently  suft'ers  from  a 
temporary  return  of  the  cncephalitic  symptoms.  If  toj)ical 
symptoms  are  left  behind  ob\i()usly  they  may  interfere  with 
the  animal's  efficiencv. 


ENCEPHALITIS— I XFLAMMATIOX  OF    THE   BRAIN     223 

Diagnosis. — The  diagnosis  depends  upon  the  symptoms  of  a 
severe  brain  disturbance  with  which  is  associated  well-defined 
topical  symptoms  such  as  hemiplegia,  monoplegia,  ataxia, 
facial  paralysis,  etc.  If  these  s^Tnptoms  occur  with  or  follow 
an  uifectious  disease  with  which  a  non-suppurative  encepha- 
litis is  apt  to  occur  a  diagnosis  is  possible.  On  the  other  hand, 
primary  encephalitis  is  quite  difficult  to  diagnose  unless  both 
the  general  and  topical  symptoms  are  well  developed.  From 
purulent  encephalitis  the  non-suppurative  form  can  usually 
be  distinguished  by  the  absence  of  injury  to  the  cranium  or 
the  absence  of  a  primary  abscess  in  some  removed  organ 
or  in  the  cranial  wall.  It  may  be  impossible  to  distinguish 
between  encephalitis  and  meningo-encephalitis  in  those  cases 
of  encephalitis  in  which  the  topical  symptoms  fail.  Further- 
more, in  some  cases  of  encephalitis  the  meninges  may  be  also 
involved.  Encephalitis  is  distinguished  from  clironic  hydro- 
cephalus by  its  more  sudden  development,  the  severity  of  the 
brain  symptoms,  and  the  presence  of  topical  symptoms. 
Encephalitis  usually  follows  some  infectious  disease.  From 
forage  poisoning  encephalitis  is  distinguished  by  the  severity 
of  the  brain  symptoms,  the  sporadic  appearance  of  the  dis- 
ease, the  absence  of  intestinal  symptoms,  and  no  history  of 
the  animal's  having  eaten  food  which  was  moldy  or  otherwise 
spoiled. 

Treatment. — The  treatment  is  the  same  as  for  meningo- 
encephalitis, and  is  usually  of  little  aid  to  recovery. 

Suppurative  Encephalitis  (Abscess  of  the  Brain). — Occur- 
rence.— Brain  abscesses  are  most  apt  to  occur  in  young  horses. 
In  the  other  domesticated  animals  abscess  of  the  brain  is 
extremely  rare. 

Etiology. — The  most  common  ca.use  of  abscess  of  the  brain 
is  strangles,  which  assumes  the  irregular  form  and  leads  to 
internal  metastatic  abscesses.  It  may  occasionally  residt 
from  other  infectious  diseases,  such  as  puerperal  septicemia, 
purulent  pneumonia,  infectious  pneumonia  (with  secondary 
pus  infection),  and  pyemia.  Occasionally  an  abscess  of  the 
brain  may  result  from  direct  injury  to  the  cranium  or  from 
abscesses  which  occur  in  the  neighborhood  of  the  brain.  In 
rarer  mstances  parasites  (estrus,  coenurus,  echinococcus  in 


224  DISEASES  OF  THE  BRAIN 

sheep;  Estriis  })()\is  in  cattle,  and  gastrophiliis  in  the  horse) 
are  causes. 

Symptoms.-  The  symptoms  of  brain  abscess  may  develop 
either  very  rapidly  or  fjradually.  In  the  former  case  the 
symptoms  are  acute;  in  the  hitter,  subacute.  When  the 
symptoms  develoj)  rapidly  the  ])atient  shows  fever  and  not 
infrequently  mental  excitement,  e\en  amounting  to  rabiform 
symptoms.  These  may  be  followed  by  mentiil  depression  or 
may  persist  until  the  death  of  the  animal.  The  muscles  may 
twitch  or  un(lergo  clonic  spasms;  forced  moAements  are  not 
infrequently  observed.  The  patient  usually  dies  in  a  few  days 
or  in  less  than  two  weeks.  In  other  instances,  as  noted,  the 
symptoms  develop  gradually,  the  patient  showing  disturbance 
in  consciousness,  forced  movements,  usually  walking  in  a 
circle.  There  may  be  occasional  manifestations  of  cerebral 
excitement;  e])ileptiform  attacks  with  intervals  between  dur- 
ing which  the  patient  appears  normal.  The  temperature  may 
not  be  increased,  although  usually  it  is  intermittent  or  remit- 
tent in  ty])e  (])us  tem])erature).  To])ical  symptoms,  such  as 
sudden  lilindness  in  one  or  both  eyes;  the  pupils  may  react 
unsymmetrically.  Hemiplegia  has  also  been  observed.  The 
head  of  the  patient  is  often  held  to  one  side  and  attempts  to 
straighten  it  cause  symptoms  of  excitement.  Some  patients 
show  vertigo,  irregular  gait,  and  a  tendency  to  fall  while  in 
motion.  Sometimes  pressure  on  the  i)oll  produces  epilepti- 
form con^allsions. 

Diagnosis. — ^The  diagnosis  depends  ^•ery  largely  upon  the 
history  of  the  case,  ?'.  e.,  whether  or  not  the  patient  has 
suffered  from  a  disease  of  suppurative  character  (strangles, 
})uerperal  septicemia) .  '^rhe  acute  form  of  abscess  of  the  brain 
cannot  be  distinguished  from  many  cases  of  acute  encepha- 
litis or  meningo-enccphalitis.  On  the  other  hand,  brain  abscess 
which  assumes  a  subacute  course  may  be  distinguished  by  the 
periodicity  of  the  brain  attacks  between  which  the  animal 
may  seem  in  good  health,  a  remittent  fever  (take  temperature 
for  several  days),  the  absence  of  sensitiveness  of  the  \)o\\,  and 
the  peculiar  to})ical  symptoms  shown.  As  meningo-cnce])ha- 
litis  may  also  result  from  a  primary  abscess  the  ])resence  of  such 
an  abscess  does  not  necessarily  speak  for  abscess  of  the  brain. 


INFECTIOUS  MENINGO-ENCEPHALOMYELITIS     225 

Treatment. — In  animals  little  can  be  done  to  relieve  the 
patient.  The  treatment  is  therefore  the  same  as  for  meningo- 
encephalitis. In  rare  instances  the  abscess  may  be  opened 
after  trephining  the  cranium  and  its  contents  e\-acuated. 
Obviously  the  abscess  must  first  be  located,  a  difficult  matter 
in  animals,  and  it  must  lie  superficially  if  results  are  to  be 
expected. 

INFECTIOUS  MENINGO-ENCEPHALOMYELITIS. 

BoRXA  Disease.    Enzootic  Cerebrospinal  Meningitis 
OF  Horses. 

Definition. — Enzootic  meningo-encephalomyelitis  is  an 
acute  infectious  disease  of  the  brain  and  spinal  cord  of  the 
horse  which  is  characterized  clinically  by  symptoms  of  cere- 
bral excitement  followed  by  depression,  ])aralysis  of  peripheral 
nerves,  and  general  paralysis.    It  is  usually  fatal. 

Occurrence. — The  disease  was  first  described  in  ^Yurtem- 
berg,  Germany,  in  1813.  It  is  common  in  the  State  of  Saxony, 
where,  in  1894,  it  attacked  a  number  of  horses  in  and  near 
the  city  of  Borna,  from  which  place  the  disease  derived  its 
name.  Whether  or  not  this  disease  has  ever  existed  or  does 
exist  in  the  United  States  is  in  dispute.  Some  authorities 
claim  to  have  recognized  it;  this  is  denied  by  others,  who 
believe  that  outbreaks  of  so-called  forage  poisoning  among 
horses  were  mistaken  for  it.  I'ntil  a  complete  scientific  study 
is  made  of  forage  poisoning,  which  is  probably  not  a  clinical 
entity,  this  question  will  not  be  definitely  settled. 

In  Europe  Borna  disease  is  confined  to  limited  districts 
in  which  the  disease  breaks  out  at  difierent  periods,  sometimes 
annually,  sometimes  with  several  years  between  outbreaks. 
It  is  most  apt  to  occur  following  wet  seasons.  The  disease  is 
usually  confined  to  certain  farms,  but  during  some  years 
becomes  a  more  widely  distributed  enzootic. 

Etiology. — The  cause  of  the  disease  has  not  yet  been  deter- 
mined. The  Borna  coccus  (Diplococcus  intracellularis  equi) 
has  not  been  proved  to  be  the  cause. 

Natural  Infection. — Horses  are  probalily  infected  through 
contaminated  food  and  water.  Some  authorities  believe  that 
15 


220  DISEASES  OF  THE  BRAIN 

the  infection  is  acquired  through  the  respiratory  organs. 
However,  Borna  disease  is  more  common  in  the  winter  and 
early  spring  months  than  in  summer,  the  dusty  period  of  the 
year.  It  is  possible  that  the  virus  is  voided  with  the  urine. 
The  disease  is  not  communicable.  It  is  much  more  common 
among  farm  than  city  horses. 

Necropsy. — ^Nlacroscopically  the  brain  appears  norma!,  but 
under  the  microscope  a  marked  cellular  infiltration  is  noted  in 
the  meninges,  brain,  and  spinal  cord.  Especially  typical 
changes  have  been  noted  in  the  ganglionic  cells  in  the  olfac- 
tory lobes  alnd  horns  of  Ammon  which  contain  peculiar, 
intensively  stained  bodies  within  the  cell  nucleus  ("nuclear 
inclusions"). 

Symptoms. — The  symptoms  are  varied,  but  in  general  are: 
early  fatigue,  icterus  of  the  mucous  membranes  and  digestive 
disturbances,  sometimes  amounting  to  colic  attacks.  These 
are  followed  by  symptoms  of  cerebral  excitement;  twitching 
of  the  muscles  of  the  face;  spasms  of  the  muscles  of  the  neck, 
sometimes  producing  torticollis;  occasionally  trismus,  nystag- 
mus, unequal  dilatation  of  the  pupils,  skin  hyperesthesia, 
exaggerated  reflexes,  occasionally  increased  sexual  desire,  and 
psychic  phenomena.  In  some  instances  the  patients  are 
vicious,  aggressive;  in  others  they  show  epileptiform  spasms. 
Later  the  patients  appear  depressed,  stu])id,  even  soporous, 
and  may  show  forced  movements.  Motor  paralysis  is  recog- 
nized by  a  weak,  staggering  gait,  paralysis  of  the  pharynx 
and  general  paralysis.  The  pulse,  respirations,  and  tempera- 
tures are  usually  little  affected.  In  a  few  cases  an  eczema  of 
the  skin  appears. 

Course  and  Prognosis. — The  course  is  usually  from  eight  to 
fourteen  days.  The  mortality  is  over  90  per  cent.  Those 
which  recover  are  often  left  infirm  through  blindness,  epilepsy, 
])ermanent  loin  lameness  or  they  remain  ''dummies."   . 

Treatment. — Treatment  is  of  no  avail.  As  a  preventi^•e  it  is 
recommended  to  change  the  food  and  drinking  water  and  to 
keep  the  animals  from  infested  ])astures.  Water  from  wells 
and  cisterns  which  are  contaminatetl  with  stable  see])age 
should  be  especially  a, voided. 


CHRONIC  HYDROCEPHALUS  227 

CHRONIC  HYDROCEPHALUS. 

Definition. — Clironic  hydrocephalus  is  a  brain  disorder 
common  in  horses,  but  rare  in  other  animals,  caused  by  the 
collection  of  serous  fluid  in  the  lateral  ventricles  of  the  brain. 
It  leads  tlu'ough  pressure  to  dilatation  of  the  lateral  ventricles, 
an  increase  in  the  size  of  the  brain  and  an  elevation  of  the 
intracranial  pressure.  The  condition  is  rarely  congenital, 
more  often  acquired. 

Etiology. — Two  types  of  hydrocephalus  may  be  distin- 
guished from  the  standpoint  of  etiology:  (a)  Inflammatory 
hydrocephalus,  the  result  of  acute  inflammation  of  the  brain 
of  which  it  is  a  sequela  developing  in  about  one  month.  In 
this  condition  the  fluid  is  an  exudate,  (b)  A  primary  or 
idiopathic  hydrocephalus  is  probably  of  mechanical  origin  and 
the  fluid  a  transudate.  It  may  be  due  to  a  congenital  con- 
striction or  closing  of  the  Sylvian  aqueduct.  An  inherited 
predisposition  to  this  form  of  brain  hydropsy  is  probable. 

Symptoms. — Chronic  hydrocephalus  in  the  horse  is  the 
commonest  cause  of  the  so-called  "dummy."  There  is 
usually  more  or  less  distiu'bance  in  consciousness  which  the 
animal  shows  by  a  number  of  clinical  symptoms.  The  follow- 
ing are  the  most  characteristic,  all  of  which  are  made  more 
prominent  by  \-igorous  exercise:  The  attitude  of  the  patient 
is  unphysiological,  the  head  is  held  low,  the  Imibs  are  fre- 
quently misplaced,  the  legs  being  crossed,  and  the  patient  is 
apt  to  stand  diagonally  in  the  stall.  The  patient  seems  indif- 
ferent to  its  surroundings,  is  sleepy,  the  eyelids  partially 
closed,  little  attention  is  paid  to  commands,  and  an  effort  to 
back  the  horse  is  futile.  The  heart  action  is  slow,  the  pulse 
in  some  cases  dropping  to  20  to  .30,  although  it  retains  its 
normal  softness.  The  symptoms  of  depression,  appearing 
from  time  to  time,  are  due  to  a  rise  of  intracranial  press- 
ure. Periods  of  excitement  may  occur  which  cause  the 
animal  to  show  s^Tiiptoms  as  in  the  stage  of  excitement 
in  acute  inflammation  of  the  lirain.  The  appetite  of  the 
"dummy"  is  often  impaired  and  the  prehension  of  food 
unphysiological.  Eating  is  cjuite  frecpiently  interrupted,  the 
animal  apparently  forgetting  for  the  moment  that  it  is  at  a 


228  DISEASES  OF  THE  BRAIN 

meal.  In  drinking  the  head  is  often  projected  n\)  to  the  eyes 
in  water;  in  some  instances  the  animal  tries  to  "eat"  rather 
than  drink  the  water.  As  noted  these  symptoms  are  usually 
emphasized  by  exercise  until  the  animal  is  in  a  profuse  sweat. 
Occasionally  syni})t()ms  of  vertigo  and  syncope  occur.  The 
skin  reflexes  (snap])ing  the  forehead,  ])oking  a  flnger  in  the 
ear,  treading  upon  the  coronet)  are  either  diminished  or  may 
in  some  cases  be  exaggerated.  In  driving  a  "dummy"  some- 
times the  animal  tends  to  go  to  the  left  or  right  of  the  road 
notwithstanding  the  effort  of  tlic  (lri\cr  to  ])revent  it.  The 
gait  is  often  abnormal,  the  animal  walking  as  if  in  water,  with 
a  high  wading  movement  of  the  fore  limbs,  or,  on  the  other 
hand,  it  may  frequently  stiunble,  setting  its  feet  down  in  an 
uncertain  fashion. 

Course. — The  course  is  chronic  and  accomjmnied  b\'  many 
exacerbations  and  remissions.  The  animal  may  live  for  many 
months  or  even  years,  showing  improvement  in  cold  and 
becoming  worse  in  warm  weather.  In  exce])tional  cases  it 
may  even  refuse  to  eat  and  die  of  starvation.  It  is  remark- 
able how  often  the  condition  as  to  flesh  is  retained  notwith- 
standing a  very  variable  a])])etite  and  the  relatively  small 
quantity  of  food  consumed. 

Prognosis. — The  jirognosis  is  bad  as  far  as  producing  healing 
is  concerned.  However,  many  "  dummies"  can  render  service 
at  slow  work  and  especially  during  cool  weather  for  months  or 
even  years.  In  time,  however,  through  gradual  mental  and 
locomotor  disturbances,  their  usefulness  ceases,  and  even- 
tually they  are  destroy efl. 

Treatment.— Treatment  is  of  no  a\ail.  The  efficiency  of  the 
anunal  may,  however,  be  prolonged  by  feedmg  only  light 
laxative  food  and  giving  the  ]mtient  good  care.  To  relie\'e 
consti])ation,  salts  should  be  given,  and  during  an  exacerba- 
tion, hypodermic  injections  of  iiilocarpin  (gr.  iv-vj)  or 
arecalin  (gr.  j-ij)  afl'ord  relief. 

BRAIN  TUMORS. 

In  animals  brain  tumors  are  comparatively  rare.  In  the 
horse  the  cholesteatoma  has  been  noted  (piite  fre(|uently  on 
necropsy.     During  life  it  rarely  produces  symptoms.    The 


GID—CCENUROSIS  229 

tumor  varies  in  size  from  a  pea  to  a  hen's  egg.  Other  tumors 
occurring  in  the  brain  substance  are  ghomas,  gliosarcomas, 
mehmosarcomas,  and  very  rarely  carcinomas.  Some  of  the 
chronic  infectious  diseases  may  produce  growths  in  the  brain 
such  as  tuberculosis,  actinomycosis  and  botryomycosis. 

In  the  meninges,  fibromas,  lipomas,  angiomas,  sarcomas, 
epitheliomas,  papillomas,  and  dermoid  cysts  have  been  noted. 

Symptoms.- — Due  to  the  slow  growth  of  brain  tumors  they 
rarely  produce  any  symptoms  during  life.  A  tumor  the  size  of 
a  hen's  egg  (melanoma)  has  been  found  in  the  brain  of  a  horse 
without  the  animal  seeming  in  any  way  disturbed  by  it. 

In  rare  instances  brain  tumors  may  produce  periodical 
increases  in  intracranial  tension,  especially  after  vigorous 
exercise,  causing  symptoms  of  transient  cerebral  excitement, 
followed  by  depression,  or  the  patient  may  show  symptoms  of 
chronic  hydrocephalus.  ^lore  rarely  the  symptoms  closely 
simulate  acute  meningo-encephalitis  or  encephalitis,  the 
animal  dying  in  a  short  time.  Sometimes  brain  tumors  pro- 
duce epileptiform  seizures,  cerebral  ataxia,  forced  movements, 
hemiplegia,  blindness,  and  an  abnormal  carriage  of  the  head. 
Congestion  of  the  papilla  is  thought  by  some  observers  sig- 
nificant of  brain  tumor,  and  is  a  probable  cause  of  the  blind- 
ness (amaurosis). 

Diagnosis. — The  diagnosis  is  obviously  extremely  difficult. 
The  gradual  development  of  the  symptoms,  both  general  and 
topical,  the  congestion  of  the  papilla,  and  the  absence  of 
fever  point  to  the  condition.  In  rare  cases  in  which  the  tumor 
leads  to  a  deformity  of  the  cranium  the  diagnosis  is  easier. 
The  clinical  symptoms  of  chronic  hydrocephalus,  chronic 
meningo-encephalitis,  abscess,  and  parasites  of  the  brain  so 
closely  resemble  those  of  tumor  in  many  cases  that  an  accu- 
rate diagnosis  becomes  impossible. 

Treatment. — Treatment  for  brain  tumor  in  animals  is  rarely 
of  avail.    In  man  they  are  occasionally  removed  surgically. 

GID.     CGENUROSIS. 

Definition. — Gid  is  a  chronic  parasitic  disease  of  sheep  and 
cattle,  due  to  the  presence  of  the  Coenurus  cerebralis  in  the 
brain  and  very  rarely  in  the  spinal  cord. 


230  DISEASES  OF  THE  BRAIN 

Natural  History. — Ca'uiirus  cerebralis  is  tlie  cyst  form  of 
the  tapeworm  TaMiia  coenurus.  The  a(Uilt  worm  is  harliored 
by  dogs,  principally  sheplierd  and  butcher's  dogs.  Occasion- 
ally wolves  and  foxes  are  hosts.  The  infestation  of  sheep  and 
cattle  takes  place  by  their  ingesting  the  eggs  or  proglottides 
which  are  voided  with  the  feces.  The  shell  of  the  egg  is 
dissolved  in  the  abomasum  allowing  the  six-hooked  embryo  to 
escape.  The  embryos  perforate  the  bowel  wall  and  ])robably 
through  the  bloodvessels  reach  the  brain  and  spinal  cord 
where  they  produce  a  hemorrhagic  leptomeningitis  and  in 
some  instances  a  purulent  infection.  They  ultimately  develop 
into  cysts  from  the  size  of  a  pigeon's  to  a  hen's  egg.  The 
cyst  produces  atrophy  of  the  brain  tissue  surrounding  it  and 
also  of  the  overly hig  skull. 

Occurrence. — While  gid  is  conamon  in  some  districts  abroad 
it  is  a  comparatively  rare  disease  in  the  Ignited  States, 
although  isolated  outbreaks  have  occurred  in  various  parts  of 
this  country.  Sheep  are  much  more  commonly  infested  than 
cattle,  in  which  it  is  a  very  rare  disease.  Young  sheep  are 
more  susceptible  than  aged  ones. 

Symptoms  in  Sheep. — From  a  clinical  standpoint,  and  due 
to  the  de\'elopment  of  the  parasite  in  the  brain,  three  stages 
of  the  disorder  may  be  determined:  (a)  The  stage  of  acute 
cerebral  inflammation,  (6)  the  stage  of  latency  due  to  the 
gradual  growth  of  the  cyst,  and  (f)  the  stage  of  gid,  the  cyst 
being  completely  developed. 

The  stage  of  brain  irritation  sets  in  from  one  to  two  weeks 
after  infestation,  and,  as  a  rule,  lasts  about  one  week.  Usu- 
ally this  stage  is  overlooked  by  the  she]iherd,  as  most  com- 
monly the  symptoms  are  not  marked.  Otherwise  the  sheep 
present  symptoms  of  excitement,  fright,  forced  movements, 
and  even  convulsions;  or,  on  the  other  hand,  may  show  lan- 
guor, stupor,  irregular  gait,  and  more  rarely  maniacal  symp- 
toms. 

In  the  stage  of  latency,  which  lasts  from  three  to  six 
months,  the  patient  appears  normal. 

The  gid  stage  usually  develops  in  winter  or  early  spring, 
and  lasts  about  one  month.  In  this  stage  the  ])atient  shows 
mental  or  motor  disturbance  and  often  to])ical  symptoms. 


INFECTIOUS  BULBAR  PARALYSIS  231 

Quite  commonly  the  first  symptoms  noted  is  that  of  mental 
disturbance.  The  sheep  appear  stupid,  and  in  some  instances 
act  like  a  horse  with  chronic  hydrocephalus.  Later  charac- 
teristic forced  movements  appear,  the  sheep  running  around 
in  circles,  trotting  across  the  field  with  head  up  and  high 
knee  action  or  they  may  roll  over  the  long  axis  of  the  body 
using  a  limb  or  the  head  as  a  pivot.  Sometimes  the  sheep 
falls  suddenly  on  its  side  or  may  fall  over  backward,  the 
head  being  held  high,  with  spasms  of  the  muscles  of  the  neck. 
Epileptiform  convulsions,  nystagmus,  strabismus,  and  blind- 
ness are  occasional  symptoms.  In  rare  instances  a  soft, 
fluctuating  area  appears  at  the  top  of  the  skull  which,  if 
punctured,  discharges  a  clear  fluid.  The  disease  usually  leads 
to  death  through  brain  paralysis  and  inanition. 

Treatment. — ^The  most  important  is  the  prophylaxis  which 
consists  in  driving  out  the  tapeworm  from  the  dog  and  pre- 
venting dogs  from  obtaining  the  brains  of  sheep  containing 
the  cyst.  An  operative  treatment  consists  in  trephining  and 
trocaring  the  cranium  over  the  seat  of  the  cyst  and  removing 
its  contents. 

INFECTIOUS  BULBAR  PARALYSIS. 
Infectious  Itching  Disease.    j\Iad  Itch.    Pseudorabies. 

Definition. — A  peculiar  infectious  disease  which  manifests 
itself  mainly  by  marked  pruritus  of  the  skin,  nervous  irri- 
tability and  sometimes  paralysis  of  the  throat  and  general 
paralysis. 

Occurrence. — Bulbar  paralysis  was  first  definitely  recog- 
nized in  Hungary  in  1902.  The  disease  has  been  noted  in  the 
United  States,  especially  in  the  Southern  States  (Alabama), 
where  it  is  much  confused  with  rabies. 

Etiology. — ^The  cause  of  the  disease  is  unknown.  It  may  be 
readily  transmitted  by  inoculating  brain  tissue  from  animals 
which  have  died  of  it  into  healthy  cattle,  sheep,  and  goats. 
Horses  and  asses  do  not  seem  to  be  as  susceptible  to  artificial 
inoculations  as  other  animals.  Dogs,  cats,  rabbits,  guinea- 
pigs,  rats,  and  mice  also  acquire  the  disease  when  injected 
with  virulent  material.    The  virus  seems  most  potent  in  the 


232  DISEASES  OF  THE  BRAIN 

tissue  at  the  ])oiiit  of  inoculation,  next  in  the  l)lood,  and  then 
in  the  central  nervous  organs.  Bile,  saliva,  and  urine  do  not 
seem  to  be  infecti\e.  The  virus  does  not  pass  through  fine 
porcelahi  filters.  Infection  through  the  digestive  tract  has 
heen  produced. 

Symptoms. — In  horses  and  nuiles  the  first  symptom  is 
usually  an  itching  of  the  skin,  especially  about  the  head, 
which  causes  the  patient  to  rub  the  part  often  so  violently 
tliat  it  may  be  denuded  of  hair,  excoriated,  or  even  lacerated. 
Tlie  ])atients  are  further  excitable,  irritable,  show  dysphagia, 
salivation,  gritting  of  the  teeth,  and  finally  paralysis.  The 
temperature  usually  does  not  rise  much  above  normal. 

In  cattle  the  infection  generally  a])pears  about  the  head, 
lips,  and  nose  which  parts  the  animal  rubs  violently,  producing 
hemorrhage  and  inflammatory  swellings  which  extend  over 
the  head,  throat,  and  sometimes  the  neck.  The  patient  is 
restless,  moves  its  legs  convulsively,  keeps  rul)bing  the  head 
against  objects,  or  scratches  it  with  its  hind  feet.  Salivation 
and  inability  to  swallow  are  often  noted.  In  some  cases  the 
digestion  is  imparied,  the  patient  showing  flatulency.  The 
animals  usually  die  in  one  or  two  days  after  the  first  symp- 
toms a])])ear. 

Course  and  Prognosis. — The  course  is  ra])id,  the  patients 
dying  within  twenty-four  to  thirty-six  hours.  The  prognosis 
is  bad ;  nearly  every  case  dies. 

Diagnosis. — The  diagnosis  during  tlie  life  of  the  ])atient  is 
not  so  easy  on  account  of  the  similarity  of  the  disease  to 
rabies.  However,  the  patient  with  bulbar  ])aralysis  does  not 
show  the  aggressive  and  destructi\'e  tendencies  of  the  rabid 
animal  and  the  symptom  of  pruritus  is  much  more  marked; 
on  postmortem  Negri  bodies  are  absent;  animals  inoculated 
usually  die  more  rapidly  (rabbits  in  convulsions  in  one  to 
three  days),  and  the  saliva  is  not  infective. 

Treatment. — Treatment  is  rarely  of  avail.  It  is  recom- 
mended to  ap])ly  tincture  of  iodin  to  the  skin  lesions,  and  if 
possible  to  so  tie  the  animal  that  it  cannot  bite  and  rub  itself. 
Edematous  swellings  may  be  scarified  and  iodin  injected. 

Believing  that  Rhus  toxicodendron  (three-leaved  poison 
ivy)  or  the  shrub  Rhus  vernix  might  be  etiological  factors. 


INFECTIOUS  BULBAR  PARALYSIS  233 

Cary,  of  Alabama,  recommends  that  these  plants  be  eradi- 
cated from  pasture  fields  or  that  animals  be  kept  from  pas- 
tures containing  them.  He  also  suggests  the  use  externally  of 
permanganate  of  potash  solution  (1  per  cent.)  two  or  three 
times  daily.  Internally,  Epsom  salts  or  raw  linseed  oil  are 
recommended . 


CHAPTER   II. 
DISEASES  OF  THE  SPIXAL  ("ORD. 

TRAUMATIC  INJURY  OF  THE  SPINAL  CORD. 

Contusion    of    the    Cord.     "Broken    Neck." 
"Broken  Back." 

Definition. — A  bruising  or  laceration  of  the  cord  due  to 
direct  or  indirect  injury  and  usually  the  result  of  fracture  of 
vertebra?. 

Occurrence.^ — Traumatic  injury  to  the  cord  is  not  uncom- 
mon in  horses.  Occasionally  it  occiu's  among  cattle  and  more 
rarely  in  swine  and  sheep. 

Etiology. — It  is  usually  due  to  falls,  l)lows,  and  in  horses 
from  struggling  in  the  hopples,  especially  if  the  animal  is 
permitted  to  arch  the  back  and  neck  upward,  the  head  not 
being  held  pro])erly.  Eitlier  fracture  or  dislocation  of  verte- 
bra? results,  leading  to  sudden  i)ressure  upon  the  cord  with 
bruising  and  sometimes  laceration.  In  some  instances  osteo- 
porosis of  the  vertebrae  predisposes  to  fracture;  \ery  rarely 
a  fissure  of  the  vertebrae  exists.  Obviously  a  hemorrhage  into 
the  cord  occurs.  In  rare  instances  the  injury  to  the  cord  is 
due  to  the  blood-clot  alone,  neither  dislocation  nor  fracture  of 
the  vertebra?  having  taken  place. 

Symptoms. — The  symptoms  will  depend  upon  what  part  of 
the  cord  is  injured  and  the  degree  of  injury.  If  the  cervical 
portion  between  the  medulla  oblongata  and  the  origin  of  the 
fifth  and  sixth  cervical  nerves  is  invohed  and  the  cord  com- 
pletely crushed,  the  patient  will  die  almost  immediately  from 
respiratory  arrest.  If  only  a  part  of  the  cord  is  crushed,  how- 
ever, it  is  possible  for  the  patient  to  li\e  se\eral  hours  or 
even  weeks  after  the  accident.  It  will  sliow  symptoms  of 
paralysis  behind  the  seat  of  injury,  dysphagia,  dyspnea,  and 
slow  pulse. 

If  the  cord  is  crushed  just  behind  the  origin  of  the  phrenic 


TRAUMATIC  INJURY  OF  THE  SPINAL  CORD     235 

nerve  a  paralysis  and  anesthesia  of  the  parts  behind  will 
result.  Breathing  will  be  performed  by  the  diaphragm,  the 
ribs  remaining  stationary.  The  patient  will  also  show 
paralysis  of  the  bowels,  bladder,  and  tail  which  becomes  as 
limp  as  a  dish-rag  ("dish-rag  tail").  The  pupils  may  be 
unequally  dilated  but  react  to  light. 

If  the  cord  is  crushed  in  its  thoracic  portion  the  symptoms 
are  the  same  except  that  the  foreparts  of  the  animal  are  not 
paralyzed  and  the  ribs  are  employed  in  respirations. 

In  the  lumbar  portion  of  the  cord  the  sjanptoms  are  similar 
except  that  the  paralysis  is  confined  to  the  hind  limbs,  tail, 
rectum  and  bladder. 

For  a  time  after  the  injury  to  the  cord  the  patient  may 
show  profuse  sweating,  marked  dyspnea  and  spasmodic  con- 
tractions of  the  muscles  in  the  neighborhood  of  the  injury. 
In  large  animals  sensitiveness  along  the  fracture  is  rarely 
noted  and  crepitation  cannot  usually  be  determined.  Obvi- 
ously anesthesia  exists  behind  the  point  of  lesion. 

Course  and  Prognosis. — Nearly  all  cases  of  fracture  or  dislo- 
cation of  vertebrae  are  fatal.  In  horses  and  cattle  death 
usually  ensues  within  forty-eight  hours.  Some  cases  of 
apparent  recovery  suffer  relapse  and  death  from  subsequent 
dislocation  of  broken  fragments  or  the  formation  of  masses  of 
callous  which  encroach  upon  the  cord. 

Diagnosis. — As  a  rule  the  diagnosis  is  not  difficult,  especially 
where  there  has  been  a  history  of  direct  or  indirect  injury. 
The  bilateral  paralysis  and  anesthesia  occurring  immediately 
behind  the  aft'ected  area,  the  limp  tail  and  the  rapid  develop- 
ment of  the  symptoms  are  significant.  From  the  standpoint 
of  differential  diagnosis  fracture  of  the  pelvis  (no  anesthesia, 
tail,  rectum,  or  bladder  paralysis)  and  azoturia  (history,  no 
tail  paralysis,  dark  urine)  should  be  thought  of. 

Treatment. — Treatment  is  of  no  avail.  Cases  which  recover 
are  usually  the  result  of  hemorrhage  only  into  the  cord.  With 
valuable  animals  it  is  sometimes  advisable  to  wait  one  or  two 
days  before  dispatching  the  patient,  to  determine  whether  or 
not  the  symptoms  arise  from  irreparable  crushing  of  the  cord 
or  a  blood-clot.  In  the  latter  case  approaching  recovery  is 
manifested  by  a  rather  rapid  disappearance  of  the  sjTuptoms. 


236  DISEASES  OF  THE  SPINAL  CORD 


INFLAMMATION    OF    THE   COVERINGS    OF   THE   CORD. 

Acute  Spixal  ^Meningitis.    Meningomyelitis. 

From  a  pathological  standpoint  ma}'  be  distinguished:  (a) 
Spinal  meningitis,  an  inflammation  of  the  meningeal  cover- 
ings of  the  cord.  If  the  hard  spinal  membrane  is  involved,  a 
spinal  pachymeningitis  is  spoken  of;  if  the  soft  a  spinal 
leptomeningitis.  (6)  ]\Iyelitis,  an  inflammation  of  the  sub- 
stance of  the  cord.  In  practice  the  inflammation  so  commonly 
involves  both  the  cord  and  its  coverings  that  the  term 
meningomyelitis  is  usually  most  a])plicable  to  the  condition. 

Occurrence. — Spinal  meningitis  is  a  rather  rare  disease  in 
liorses  except  when  it  occasionally  assumes  an  enzootic  dis- 
tribution.* 

Etiology. — The  principal  cause  of  spinal  meningitis  is  in- 
fection. The  condition  is  rarely  secondary  to  acute  infectious 
diseases  such  as  infectious  pneumonia  of  the  horse,  strangles, 
pyemia  and  septicemia .  It  may  also  result  from  inflammation 
which  exists  in  the  neighborhood  of  the  cord,  such  as  caries 
of  the  vertebra,  abscesses  which  erupt  into  the  vertebral 
canal  and  it  is  possible  that  infection  may  be  carried  along  the 
nerve  trunks  to  the  cord  and  its  coverings.  A  primary  spinal 
meningitis  may  be  occasionally  the  result  of  traumatism  such 
as  a  blow  over  the  back,  or  rarely  where  a  horse's  tail  is 
docked  too  closely.  In  very  rare  instances  shar]>-]:)ointed 
foreign  bodies  which  have  been  swallowed  by  cuttle  have 
wandered  into  and  injured  the  cord.  The  form  of  inflamma- 
tion may  be  either  serofibrinous  or  sup])m'ative. 

Symptoms. — The  gait  of  the  animal  alVected  is  usually  stiff, 
straddling  and  laliored.  In  the  first  stages  the  skin  over 
certain  areas,  especially  in  the  region  of  the  back,  is  extremely 
sensitive.  Stroking  the  animal  in  a  direction  contrary  to  the 
lay  of  the  hair  causes  severe  pain,  the  patient  arching  the 
back,  becoming  restless  and  making  every  efl'ort  to  evade  the 
examiner.  Striking  the  tops  of  the  spines  of  the  vertebrae 
with  the  handle  of  a  percussion  hammer  may  cause  the 
animal  to  evince  pain. 

Groups  of  muscles  show  twitching  or  more  marked  spasm- 


INFLAMMATION  OF  COVERINGS  OF  THE  CORD       237 

like  contractions  which  are  usually  initiated  whenever  the 
skin  is  touched.  In  some  instances  the  patient  is  so  sensitive 
that  it  may  rear  into  the  air.  The  muscles  of  the  back  and 
neck  appear  firm  and  extremely  tender.  If  the  abdominal 
muscles  are  involved  the  respirations  are  rapid  and  super- 
ficial. Urination  and  defecation  are  painful  and  difficult.  In 
some  cases  spasm  of  the  sphincters  of  the  bladder  and  anus 
produce  retention  of  urine  and  feces.  In  rare  instances  in 
male  animals  priapism  occiu's. 

As  the  cord  substance  usually  becomes  in\'olved  later, 
paralyzing  the  roots  of  the  motor  nerves,  paralysis  of  muscle 
groups,  diminished  reflexes,  and  decreased  sensibility  occur. 
In  the  latter  stages  the  animal  becomes  paralyzed,  the  par- 
alysis involving  all  parts  of  the  body  behind  the  cord  lesion. 
The  temperature  of  the  patient  is  usually  increased. 

Course. — As  a  rule  death  ensues  within  a  week.  When  the 
inflammation  is  confined  to  circumscribed  areas  of  the  cord 
the  patient  may  live  for  months. 

Diagnosis.^ — If  the  disease  develops  typically  and  each  stage 
can  be  observed  a  diagnosis  usually  can  be  made.  The 
gradual  diminution  of  the  symptoms  of  extreme  skin  sen- 
sitiveness and  muscle  spasms  in  the  region  of  the  spinal 
nerves,  the  recognizable  spread  of  the  inflammation  along  the 
course  of  the  cord  and  the  presence  of  a  primary  disease  in 
the  neighborhood  of  the  spinal  canal  are  significant.  The 
peculiar  course  differentiates  spinal  meningitis  from  con- 
tusion of  the  cord.  From  the  standpoint  of  differential 
diagnosis  muscular  rheumatism,  laminitis  and  tetanus  should 
be  thought  of.  From  acute  muscular  rheumatism  the  marked 
sensitiveness  of  the  skin  seen  in  spinal  meningitis  is  signi- 
ficant; in  laminitis  the  presence  of  foot  symptoms,  and  in 
tetanus  the  absence  of  sensory  disturbances  and  the  pro- 
lapse of  the  nictating  membrane  when  the  head  is  elevated, 
serve  for  differentiation.  A  distinction  between  spinal  menin- 
gitis and  myelitis  is  not  always  possible.  However,  myelitis 
is  characterized  by  sensory  and  motor  paralysis  with  which  is 
usually  associated  paralysis  of  the  bladder  and  rectum  and 
does  not  present  symptoms  of  hyperalgesia  and  muscular 
spasms. 


238  DISEASES  OF  THE  SPINAL  CORD 

Treatment. — The  patient  should  be  made  as  comfortable  as 
possible.  Horses  should  be  given  deep  bedding  and  the 
j)aralyzed  parts  kept  scrupulously  clean  and  protected  to 
avoid  decubitus.  If  the  conditions  permit  a  sling  may  be 
used.  Internally  salicylate  of  sodium  (5ss)  or  calomel  (3j) 
may  be  used.  When  the  pain  is  very  great  and  the  spasms  of 
the  muscles  marked,  narcotics  such  as  chloral  hydrate  or 
morphin  may  be  administered. 

INFLAMMATION  OF  THE  SUBSTANCE  OF  THE  CORD. 

Spinal  Myelitis. 

Definition. — Spinal  myelitis  is  an  inflammation  of  the  sub- 
stance of  the  cord  usually  due  to  infection  or  intoxication. 

Occurrence. — Spinal  myelitis  is  a  rare  disease  in  horses  and 
cattle. 

Etiology. — It  is  usually  secondary  to  influenza,  rabies, 
rarely  to  tuberculosis  in  the  ox,  and  still  more  rarely  to 
strangles.  In  so-called  forage  ])ois()ning  of  horses  occasion- 
ally myelitis  has  been  noted.  In  many  instances  no  cause 
can  be  determined.  Refrigeration,  overexertion,  and  abuse 
of  the  sexual  organs  are  probably  only  ])redisposing  factors. 

Symptoms.  ~  Three  forms  of  myelitis  are  described  from  a 
clinical  standpoint,  viz.:  (a)  transverse,  (b)  disseminated,  and 
(c)  diffuse.  In  animals  a  differentiation  among  these,  how- 
ever, is  not  always  possible.  The  s\nnptoms  of  myelitis  are 
dependent  upon  the  site  and  extent  of  tlu;  si)inal  inflammation 
and  vary  accordingly. 

Transverse  Myelitis. — A  focal  lesion  affecting  more  or  less 
completely  the  whole  transverse  area  of  the  cord.  Depending 
upon  whether  the  cervical,  dorsal,  or  lumbosacral  regions  are 
involved  the  symptoms  will  A-ary. 

The  sensory  and  motor  disturbances  usually  develop  gradu- 
ally. For  a  time  the  animal  may  show  only  early  fatigue 
when  at  work,  may  lie  down  frequently  and  rise  to  its  feet 
with  difliculty.  Later  the  gait  becomes  irregular  ])e]iin(l,  the 
animal  seeuis  "weak  in  the  back,"  and  frequently  knuckles 
in  the  hind  fetlock.  Later  it  may  become  completely  par- 
alyzed behind  the  ]w'mi   of  lesion.     Horses  may  therefore 


INFLAMMATION  OF  SUBSTANCE  OF  THE  CORD     239 

assume  a  sitting  posture ;  cattle  and  small  animals  may  drag 
the  hind  parts.  The  skin  and  tendon  reflexes  may  be  exag- 
gerated, especially  if  the  myelitis  has  developed  gradually 
and  the  paralysis  be  of  spastic  type;  or,  on  the  other  hand, 
they  may  be  greatly  diminished,  the  muscles  involved  lose 
tone,  become  flabby,  and  no  longer  contract.  The  bladder, 
rectum,  and  tail  eventually  become  paralyzed,  leading  to 
incontinence  of  urine  and  feces  and  the  development  of  a 
limp  tail.  Provided  the  animal  live  long  enough,  there  usually 
later  develops  atrophy  of  groups  of  muscles.  Edema  of  the 
skin  and  diffuse  sweating  have  also  been  noted. 

Disseminated  Myelitis. — This  should  be  regarded  more  as  a 
multiple  of  the  transverse  type  than  as  a  separate  disease.  It 
is  very  rare  in  animals.  Depending  upon  the  seat,  size,  and 
number  of  inflammatory  foci  the  symptoms  vary.  In  some 
instances  they  are  identical  with  transverse  myelitis.  A 
diagnosis  is  only  possible  when  the  patient  manifests  a  cir- 
cumscribed motor  and  sensory  paralysis  which  may  be  con- 
fined to  one  hind  limb  or  to  certain  groups  of  muscles.  Not 
infrequently  the  muscles  involved  may  show  rhythmic  twitch- 
ings  or  contractions.  In  the  horses  a  string-halt-like  move- 
ment of  a  limb  has  been  noted.  In  the  dog  a  desire  to  gnaw 
at  a  part  until  it  became  mutilated  has  been  observed. 

Diffuse  Myelitis. — This  is  sometimes  spoken  of  as  ascend- 
ing or  descending  myelitis.  It  is  characterized  by  progressive 
paralysis,  motor  and  sensory,  usually  beginning  in  the  hind 
limbs,  croup  and  tail  and  gradually  involving  the  whole  of 
the  body  as  the  paralysis  progresses  anteriorly.  Conversely 
it  may  begin  anteriorly  and  spread  toward  the  tail. 

Course  and  Prognosis. — The  course  depends  upon  the  seat 
and  the  rapidity  of  extension  of  the  inflammation.  Trans- 
verse and  diffusa  myelitis  usually  end  fatally  in  a  short  time 
while  disseminated  myelitis  may  last  for  months.  Death 
usually  results  from  septicemia  (decubitus),  inflammation  of 
the  paralyzed  bladder  and  bowel,  tor  in  some  cases  from 
respiratory  arrest.    Recovery  is  very  rare. 

Diagnosis. — The  diagnosis  of  spinal  myelitis  depends  upon 
the  presence  of  cord  symptoms  without  history  of  injury. 
The  absence  of  extreme  skin  sensitiveness  and  muscular 


240  DISEASES  OF  THE  SPINAL  CORD 

spasm  differentiates  it  from  traumatic  injury.  From  mus- 
cular weakness  attendinji^  general  diseases  which  do  not 
involve  the  cord,  the  condition  may  be  differentiated  by  the 
absence  in  these  of  any  sensory  disturbance,  bladder,  rectum 
or  tail  paralyses. 

Treatment. — The  treatment  is  rarely  satisfactory.  The 
patient  should  be  provided  Avith  a  clean,  deep  bed.  Slings 
may  be  used  when  feasible.  The  bladder  and  rectum  may 
be  emptied  manually.  Every  effort  should  be  made  to  avoid 
decubital  gangrene.  Drugs  such  as  iodid  of  potash,  strychnin 
or  arsenic  do  little  or  no  good.  Constipation  may  be  relieved 
by  subcutaneous  injections  of  arecalin  (gr.  j)  and  rectal 
infusions.  Electricity  is  much  employed  but  little  is 
to  be  expected  from  it.  As  a  rule  it  pays  to  dispatch  the 
patient. 

COMPRESSION  OF  THE  SPINAL  CORD. 

Definition. — A  condition  whereby  the  cord  is  pressed  upon 
by  a  growth,  tumor,  abscess  or  parasite  which  invades  the 
vertel)ral  canal. 

Occurrence. — Compression  of  the  cord  is  comparatively 
rare  in  large  animals.  Occasional  cases  are  recorded  in  horses, 
cattle  and  swine. 

Etiology. — Tlie  following  pathological  conditions  may  lead 
to  compression  of  the  cord : 

(a)  Ossification  of  the  intervertebral  disks :  Occasionally  in 
old  horses  a  senile  ossification  occurs  and  if  the  ossified  disc 
happens  to  protrude  into  the  hunen  of  the  vertebral  canal, 
compression  of  the  cord  results. 

(6)  Inflammatory  gro^^'ths:  In  swine  tuberculosis  and  in 
cattle  tuberculosis  and  actinomycosis  of  the  vertebrae  may 
involve  the  vertebral  canal  and  encroach  upon  the  cord. 
Occasionally  the  tuberculosis  may  develop  upon  the  meninges 
of  the  cord  with  similar  results.  In  very  rare  instances 
tuberculosis  in  the  horse  may  involve  the  cord.  ]\Iore 
commonly  glanders  of  the  vertebral  column"  may  affect 
the  cord. 

(c)  Tumors:  Jiarely  do  tumors  cause  compression  of  the 


COMPRESSION  OF   THE  SPINAL  CORD  241 

cord.  Generally  the  tumor  develops  in  the  neighborhood  of 
the  spinal  column  (sarcoma),  proliferates  through  the  inter- 
Nertebral  openings  or  through  the  substance  of  the  vertebrae 
enters  the  canal  and  invades  the  cord.  In  gray  horses  these 
tumors  are  usually  melanotic  (melanosarcomas). 

(d)  Abscesses:  Abscesses  which  develop  in  the  neighbor- 
hood of  the  vertebral  column  may  invade  the  canal,  producing 
compression.  As  a  rule,  however,  this  is  not  the  case,  although 
the  pus  may  enter  the  canal  and  infect  the  meninges. 

(e)  Parasites :  In  cattle  and  sheep  the  Coenurus  cerebralis ; 
in  swine  cysticerci,  and  in  cattle  echinococci  invade  the  spinal 
cord.  They  rarely  produce  symptoms  during  life  and  there- 
fore have  only  a  pathological  and  sanitary  importance. 

Symptoms. — The  symptoms  in  large  animals  are  usually 
those  of  rigidity  of  the  spine  which  may  make  it  difficult  for 
the  animal  to  eat  off  the  ground  or  to  rise  from  a  recumbent 
posture.  The  gait  is  also  stiff'  and  labored.  As  a  rule  the 
patient  gradually  becomes  paralyzed  behind  the  seat  of  the 
lesion  so  that  paralysis  of  the  tail,  rectum  and  bladder 
appear. 

Course. — The  course  is  chronic.  The  paralysis,  which  is 
gradual  in  its  development,  eventually  leads  to  permanent 
recumbency  and-death  from  decubital  gangrene  (septicemia). 
In  other  cases  h^-postatic  pnemnonia  or  cystitis  may  be  the 
cause  of  death. 

Diagnosis. — The  diagnosis  is  not  easy.  The  gradual  pro- 
gressive paralysis,  anesthesia,  stiffness  of  gait,  and  atrophy 
of  muscles  are  noted  in  other  diseases  of  the  spinal  cord. 
Obviously  in  those  cases  in  which  swelling  and  pain  in  the 
neighborhood  of  the  vertebral  cohmm  occur  the  diagnosis 
is  easier. 

Prognosis. — The  prognosis  is  unfavorable.  In  rare  cases  a 
temporary  improvement  has  been  noted.  However,  usually 
this  is  followed  by  an  exacerbation. 

Treatment. — After  waiting  until  the  patient  can  be  observed 
long  enough  to  determine  that  there  is  no  hope  of  recovery  it 
should  be  dispatched.  Obviously  in  edible  animals  the  de- 
struction of  the  patient  should  be  undertaken  earlier  than  in 
horses. 
16 


242  DISEASES  OF  THE  SPINAL  CORD 

INFECTIOUS    SPINAL   PARALYSIS    OF    THE    HORSE. 
Enzootic  Paraplegia. 

Definition. — An  enzootic  spinal  paralysis  of  horses,  whicli 
usually  takes  an  acute  course  and  is  characterized  patholofji- 
cally  by  numerous  small  hemorrhages  in  the  different  organs, 
but  particularly  in  the  spinal  cord.  The  genital  organs  and 
bladder  not  uncommonly  show  gelatinous  infiltration. 

Occurrence. — The  disease  is  found  in  different  parts  of 
Europe,  occurring  mostly  among  cavalry  horses  and  in  studs. 
No  outbreaks  have  been  reported  in  the  Ignited  States. 

Etiology. — The  cause  of  the  disease  is  believed  to  be  a  strep- 
tococcus (Streptococcus  melanogenes)  which  is  found  in  the 
blood,  parenchymatous  organs,  medullary  substance  of  the 
bone,  spinal  cord,  and  in  the  gelatinous  infiltration  of  the 
genital  organs  and  bladder. 

Natural  Infection. — Horses  are  infected  probably  through 
the  digestive  tract  with  contaminated  food  and  water.  It  is 
possible  that  the  streptococcus  assumes  a  saprophytic  life 
outside  of  the  body.  Horses  of  low  resistance  may  be  first 
attacked,  and  from  them  later  others  are  infected.  The 
urine  and  feces  are  probably  infective. 

Symptoms.— A  preliminary  stage  is  characterized  by  weak- 
ness behind,  rapid  fatigue,  and  emaciation.  In  some  cases 
spasms  of  the  muscles  of  the  loins,  croup,  and  abdomen  have 
been  noted.  In  some  outbreaks  mild  edema  of  the  ])repuce 
or  vulva  has  been  observed.    The  patient  urinates  frequently. 

In  the  later  stage  of  the  disease  the  patient  may  collapse 
during  work  or  more  rarely  even  when  at  rest.  Paralysis  of 
th(>  hind  limbs  develops,  making  it  impossible  for  the  animal 
to  rise  from  a  recinnbcnt  position  or  stand  without  assistance. 
The  digestive  tract  remains  practically  intact.  In  some  out- 
breaks the  temperature  may  reach  as  high  as  107.6°  F.,  and 
the  pulse  becomes  very  rapid.  The  ])atient  may  also  show 
stranguria;  the  urhie  is  stained  red  and  contains  albumin. 
Sensibility  is  not  much  impaired,  and  paralysis  of  the  sphinc- 
ters is  little  developed.  Occasionally  there  may  be  marked 
inflammation  of  the  external  genitals.    The  penis  is  swollen, 


SPINAL  PARALYSIS  OF  THE  HORSE  243 

edematous,  and  protrudes  from  the  prepuce.  In  mares  the 
external  genitals  may  be  swollen  and  edematous. 

Course. — The  course  is  very  varied.  The  duration  of  the 
disease  may  be  from  a  few  days  to  three  months.  Con- 
valescence is  slow.  The  mortality  varies  from  50  to  100 
per  cent. 

Diagnosis. — The  paralytic  symptoms  with  little  impairment 
of  sensibility,  a  good  appetite,  the  swelling  of  the  external 
genitals,  and  the  enzootic  occurrence  of  the  disease  are  sig- 
nificant. In  sporadic  cases  only  the  determination  of  the 
streptococci  in  the  blood  would  furnish  tangible  evidence  of 
the  existence  of  the  disease.  From  the  standpoint  of  differ- 
ential diagnosis,  infectious  spinal  paralysis  might  be  confused 
with  azoturia,  infectious  anemia,  sclerostomiasis,  and  forage 
poisoning. 

Treatment. — IMedicinal  treatment  is  of  little  or  no  value. 
It  is  purely  symptomatic. 

Prophylaxis. — The  food  and  water  should  be  looked  after 
to  see  that  they  are  good  and  pure.  The  administration  of 
antistreptococcic  sera  to  healthy  but  exposed  horses  is 
thought  to  have  a  preventi^'e  action. 


CHAPTER   HI. 
FUNCTIONAL  NER\'OUS  DISEASES. 

VERTIGO, 

Definition. — Vertigo  is  a  symptom  and  not  a  disease.  It  is 
characterized  by  dizziness,  a  disorder  of  the  equiUbrating 
sense,  causing  a  feeHng  of  instabihty  and  apparent  rotary 
movement  of  the  body  or  other  objects,  ^'ertigo  is  very 
possibly,  due  to  a  disturbance  in  the  equiHl)rating  centre  in 
the  ccrebelhmi. 

Occurrence.- — Vertigo  is  not  common  in  animals,  but  is 
occasionally  seen  in  horses  and  dogs.  As  a  rule  the  heavier 
breeds  of  horses  are  aflfected. 

Etiology. — In  animals  vertigo  is  usually  secondary  to  brain 
diseases,  such  as  acute  and  chronic  encephalitis  and  epilepsy. 
It  may  also  attend  chronic  diseases  of  the  lung  and  heart,  which 
cause  venous  congestion  in  the  brain.  Compression  of  the 
jugulars  from  the  collar  of  the  harness  is  a  common  cause. 
\ertigo  is  a  symptom  of  anemia  of  the  brain;  it  can  also 
come  from  eating  poisonous  plants.  An  ocular  vertigo  is 
occasionally  seen  in  horses  due  to  light  effects,  such  as  result 
from  shiny  blinders  or  a  bright  light  shining  in  the  face  or 
occasionally  from  driving  the  horse  through  an  alley  of  trees 
which  cast  their  shadows  across  the  roadway. 

Symptoms. — The  horse  is  usually  attacked  at  work.  The 
patient  begins  throwing  and  shaking  its  head,  running  back- 
ward a  few  steps,  swaying  in  the  shafts,  and  after  staggering 
about  falls  to  the  ground,  where  it  lies  unconscious  and  (juiet 
for  from  one  to  five  minutes.  After  coming  out  of  the  attack 
the  animal  regains  its  feet  and  seems  to  be  normal  again. 

Diagnosis. — The  diagnosis  of  vertigo  is  usually  readily 
made,  but  to  determine  its  cause  is  often  extremely  difficult. 
It  may  be  distinguisiicd  from  epilepsy  by  the  absence  of 
convulsions  while  the  animal  is  down. 


EPILEPSY—FALLING  SICKNESS  245 

Treatment. — During  an  attack  the  patient  should  be  un- 
harnessed and  made  comfortable.  Some  recommend  throw- 
ing a  blanket  over  the  head.  Ice  or  cold  water  to  the  poll  is 
often  of  advantage.  If  the  cause  of  vertigo  can  be  determined 
and  removed,  permanent  healing  is  possible.  Usually  the  best 
results  are  obtained  by  changing  the  harness  to  avoid  con- 
striction of  the  jugular  veins  or  interference  with  vision. 


EPILEPSY.     FALLING  SICKNESS. 

Definition. — Epilepsy  is  a  chronic  disorder  of  the  nervous 
system,  characterized  by  attacks  of  unconsciousness  and 
spasms,  which  occur  periodically.  Between  the  attacks  the 
patient  appears  in  normal  health. 

Occurrence. — Epilepsy  is  rare  in  horses  and  cattle,  but  is 
relatively  common  in  dogs. 

Etiology. — The  causes  of  epilepsy  are  not  known.  In  true 
epilepsy  there  are  no  lesions  which  are  characteristic.  Hered- 
ity has  been  accused. 

Symptoms. — Two  forms  of  epilepsy  may  be  distinguished : 
The  severe  type  characterized  by  a  complete  epileptic  con- 
vulsion (grand  mal)  and  the  milder  type  characterized  by 
incomplete  or  partial  attacks  (petit  mal) . 

Grand  Mal — In  animals  the  epileptic  seizure  comes  about 
suddenly  and  usually  without  prodromal  symptoms  (aura 
epileptica).  The  patient  falls  to  the  ground  after  showing 
symptoms  of  dizziness,  and  is  rapidly  overcome  with  severe 
tonic  spasms  of  the  head,  neck,  body,  and  limbs.  The  jaws 
may  be  locked,  the  neck  and  back  bent  backward,  and  the 
limbs  extended.  There  are  clonic  spasms  of  the  lips  and  the 
lower  jaw,  inducing  movements  of  the  jaw  and  foamy  saliva- 
tion. The  eyes  are  rolled  in  their  sockets  and  the  limbs  move 
convulsively.  At  the  same  time  the  patient  is  unconscious, 
sensitiveness  is  lost,  and  the  pupil  dilated.  The  duration  of 
the  attack  is  only  for  a  few  minutes.  After  it  is  over  the 
animal  regains  its  feet,  seems  for  a  time  languid,  but  is  soon 
normal  again.  Between  such  attacks  the  patient  appears  in 
perfect  health.     Attacks  follow  at  very  irregular  intervals. 


24G  FUNCTIONAL  NERVOUS  DISEASES 

Epilepsy  may  exist  for  years  or  c\eii  diiriiiti  the  wliole  life 
of  the  animal. 

Petit  Mai. — The  mild  type  manifests  itself  by  spasms  of 
certain  groups  of  muscles,  usually  of  the  head  (lips,  facial 
muscles,  eye  muscles),  neck,  and  front  limbs.  This  is  accom- 
panied by  a  partial  and  temi)orary  loss  of  consciousness. 
In  some  cases  there  may  be  no  convulsions,  only  loss  of  con- 
sciousness, as  in  vertigo. 

Treatment. — No  successful  treatment  is  known  for  epilej)sy. 
In  animals  bromid  of  potash  (5j)  is  helpful. 

ECLAMPSIA. 

Definition. — A  convulsive  seizure  like  that  of  epilepsy,  but 
which  assumes  an  acute  character  and  terminates  either  in 
permanent  reco\ery  or  may  end  in  death  shortly  following  the 
attack.  The  term  eclampsia  may  be  used  in  a  broad  and  in  a 
narrow  sense:  Eclampsia  in  a  broad  sense  would  include 
brain  convulsions  or  tonoclonic  spasms,  with  loss  of  con- 
sciousness occurring  usually  in  the  course  of  acute  encepha- 
litis, influenza,  lead  poisoning,  or  uremia. 

Enclampsia  in  a  narrow  sense  would  be  the  peculiar,  acute 
epileptiform  spasms  in  suckling  animals  (eclampsia  infantum), 
and  in  mothers  which  ha^•e  just  given  birth  to  young  (eclamp- 
sia puerperal  is). 

The  most  important  type  of  eclampsia  in  animals  is 
puerperal  eclampsia,  which  is  extremely  rare  in  cows  and 
sows,  but  relatively  frequent  in  bitches.     (See  other  works.) 

CATALEPSY. 

Defijiition. — Catalepsy  is  a  peculiar  nervous  disorder,  char- 
actci-i/cd  l)y  loss  of  consciousness  combined  with  cramj)-like 
contractions  of  the  musculature  of  the  body,  which  becomes 
rigidly  fixed.  The  patients  remain  immovable  in  the  position 
placed  and  the  joints  may  be  readily  bent  passively.  At  the 
same  time  there  is  loss  of  sensitiveness  of  the  skin.  The 
cataleptic  state  has  been  noted  in  dogs.  It  is  extremely  rare 
in  animals. 


SPASMS  OF   THE  DIAPHRAGM  247 

CHOREA.     SAINT  VITUS'  DANCE. 

Definition. — Chorea,  or  Saint  Vitus'  dance,  is  an  involun- 
tary, rhythmic  twitching  of  certain  muscles,  producing  irregu- 
lar jerking  movements  usually  in  the  head,  eyelids,  and 
facial  muscles,  and  occasionally  of  the  limbs. 

Etiology. — The  cause  in  animals  seems  to  be  a  brain  neu- 
rosis. Chorea-like  twitchings  sometimes  result  from  dis- 
temper in  dogs.  This,  however,  is  a  sequela  of  encephalitis 
or  meningo-encephalitis  and  is  not  a  true  chorea. 

SPASMS  OF  THE  DIAPHRAGM. 

Definition. — A  rhythmic  spasmodic  contraction  of  the 
muscles  of  the  diaphragm,  with  which  is  usually  associated 
clonic  spasms  of  the  abdominal  muscles. 

Occurrence. — Spasms  of  the  diaphragm  are  most  frequently 
noted  in  horses.  Exceptionally  cases  have  been  described  in 
cattle. 

Etiology. — Digestive  disturbances  of  an  acute  character 
affecting  the  stomach  (acute  catarrh,  bloating),  bowels 
(catarrh  or  constipation).  \ery  probably  toxic  substances 
absorbed  from  the  gastro-intestinal  contents  reflexly  stimu- 
late the  nerves  of  the  diaphragm,  producing  the  symptoms. 
Overexertion,  especially  when  accompanied  b}'  mental  excite- 
ment (runaways,  overdriving,  pulling  an  object  of  which  the 
horse  is  afraid),  may  also  induce  it.  Acute  inflammatory 
diseases  of  the  thoracic  organs  and  pleura  may  be  occasional 
causes. 

Symptoms. — The  symptoms  are  somew^hat  similar  to  those 
of  palpitation  of  the  heart,  except  that  the  spasms  do 
not  occur  synchronously  with  the  pulse.  They  consist  in 
rhythmic,  electric-stroke-like  shocks,  which  can  be  seen  and 
felt  especially  along  the  ribs,  the  loins,  hollow  of  the  flank, 
and  over  the  chest.  If  the  hand  is  placed  upon  the  patient, 
throbs  may  be  felt  which  are  most  intensive  over  the  dia- 
phragmatic attachments.  While  coincidentally  the  number 
of  beats  may  be  equal  to  those  of  the  heart,  they  are  generally 
less  in  nmnber  (ten  to  fifteen  per  minute)  and  do  not  corre- 


248  FUNCTIONAL  NERVOUS  DISEASES 

spond  witli  the  heart  beat.  In  some  cases  synchronous 
Avith  each  si)asni  a  forced,  noisy  expiration  is  noted  at  the 
nostrils.    The  i)atient  usually  docs  not  cat  and  is  restless. 

In  cattle  trainnatic  indigestion  causing  injury  of  the 
diaphragm  may  be  attended  by  diaphragmatic  spasms. 

Course  and  Prognosis. — The  course  will  vary  from  a  few 
minutes  to  sc\cral  days;  most  cases  recover,  however,  in 
about  two  days.  Generally  speaking,  the  prognosis,  which 
de])ends  upon  the  cause,  is  favorable. 

Diagnosis. — The  rhythmic  throbs  which  produce  synchron- 
ously a  momentary  protrusion  of  the  hollow  of  the  flank 
and  epigastrium,  with  a  simultaneous  sinking  of  the  inter- 
costal spaces,  are  significant.  In  doubtful  cases  a  rectal 
exploration,  the  hand  coming  in  contact  with  the  attachment 
of  the  diaphragm,  is  assuring. 

If  the  s})asms  are  confined  to  the  abdominal  muscles  a 
marked  twitching  of  these  muscles  may  be  seen  and  felt; 
synchronous  with  them  the  epigastrium  sinks  in  and  the 
intercostal  spaces  are  })rotruded. 

Treatment. — The  patient  should  be  placed  in  a  quiet  place 
and  a  subcutaneous  injection  of  morphin  given  (gr.  iij-vj). 
Bromid  of  potash  and  chloral  hydrate  (5j)  may  be  also 
used.    Attending  digestive  disturbances  should  be  treated. 


PART  X. 

DISEASES  OF  THE  SKIN. 


ECZEMA. 


Definition. — Eczema  is  a  dermatitis  accompanied  by  exu- 
dation and  itching  invohing  the  superficial  layers  of  the 
corium. 

Course.— In  the  course  of  the  dermatitis  there  develop 
erythema,  papules,  vesicles,  and  pustules,  followed  by 
desquamation. 

Forms.— From  a  clinical  standpoint,  and  depending  largely 
upon  the  pathological  character  of  the  dermatitis,  the  fol- 
lowing forms  of  eczema  are  distinguished : 

(a)  Er\i:hematous  eczema,  an  inflammatory  congestion  of 
the  skin. 

(b)  Papulous  eczema,  characterized  by  nodules  due  to  a 
cellular  infiltration  and  swelling  of  the  papilla. 

(c)  Vesicular  eczema,  consisting  in  the  development  of 
circumscribed  areas  of  serous  exudation,  or  vesicles,  beneath 
the  external  layer  of  the  skin. 

(d)  Eczema  madidans,  red  or  weeping  eczema,  due  to  the 
rupture  of  the  vesicles  from  the  patient  biting  and  scratching 
them. 

(e)  Pustulous  eczema,  characterized  by  the  appearance  of 
vesicles  containing  pus,  or  pustules. 

(/)  Impetiginous  eczema,  originating  from  the  rupture  of 
the  pustules,  causing  the  surface  of  the  skin  aftected  to  be 
covered  with  moist  or  dry  pus. 

(gf)  Crustated  eczema,  crusts  and  scabs  forming  on  the 
skin  from  the  drving  of  the  exudate. 


250  DISEASES  OF  THE  SKIN 

(//)  Squamate  eczema,  where  tlu>  epidermis  is  covered  Avith' 
masses  of  scales, 

(0  Seborrheic  eczema,  where  the  crusts  are  infiltrated  with 
masses  of  fat  from  the  sebaceous  glands,  forming  white  or 
yellowish,  greasy  scales. 

(i)  Sycosiform  eczema,  which  is  an  inflammation  of  the 
hair  follicles,  forming  papules  or  ])ustules  that  are  perforated 
l)y  hairs. 

Etiology. — The  causes  of  eczema  are  usually  external,  and 
consist  in  mechanical,  chemical,  thermic,  and  infectious  irri- 
tants. The  most  common  of  these  is  neglect  of  skin  cleanli- 
ness. Eczema,  therefore,  is  most  often  seen  on  parts  of  the 
skin  of  the  horse  where  the  least  grooming  is  done.  On  the 
other  hand,  too  much  water  coming  in  contact  with  the  skin 
can  produce  eczema.  Examples  are  the  eczema  of  sheep  from 
ex})osure  to  excessive  rain  fall,  ett'ect  of  dewy  i)astures,  muddy 
roadways,  etc.,  upon  the  skin  of  the  legs  of  horses  or  the  too 
frequent  bathing  of  dogs.  Eczema  can  also  originate  from 
the  discharges  in  diarrhea,  incontinence  of  urine,  and  profuse 
sweating.  The  mechanical  insults  which  produce  eczema  are 
insect  bites  (fleas,  lice),  biting,  rubbing,  and  scratching  on  the 
part  of  the  patient  and  the  friction  of  the  harness  or  saddle. 
Thermic  influences  are  cold,  the  sun's  rays  (solar  eczema), 
or  fire.  Many  chemicals  can  produce  eczema,  such  as  mer- 
cury, mustard,  tobacco,  etc.,  when  applied  to  the  skin.  Mer- 
cury or  iodin  given  internally  for  a  long  i)eriod  of  time  can 
have  the  same  effect. 

Internally  eczema,  or  more  properly  exanthema,  can  be  due 
to  disturbances  in  the  digestive  tract  where  an  auto-intoxica- 
tion is  produced.  Exanthema  also  accompanies  many  in- 
fectious diseases  and  appears  associated  with  conditions  lead- 
ing to  cachexia  (lung-worm  plague  of  sheep).  Einally,  mange 
mites  produce  eczema.  In  man  certain  individuals  seem  pre- 
dis})osed  to  eczema. 

Symptoms. — The  Aarious  pathological  changes,  such  as  the 
papule,  vesicle,  pustule,  etc.,  in  eczema  can  be  noted  on  the 
living  animal.  The  process  passes  through  its  varied  stages 
rather  rapidly,  one  phase  developing  out  of  the  other.  By 
lifting  the  crusts  the  moist  areas  over  the  papillary  layer  of 


ECZEMA  251 

the  skin  are  exposed,  forming  very  characteristic  lesions.  It 
is,  further,  not  uncommon  to  see  all  or  most  of  the  different 
stages  on  the  different  parts  of  the  skin  appearing  at  the  same 
time.  Where  the  skin  has  been  rubbed,  scratched,  or  bitten 
secondary  changes  appear  which  modify  the  character  of  the 
lesions. 

Pruritus  is  a  constant  symptom  of  eczema.  In  acute  cases 
it  is  often  quite  pronounced.  If  the  eczema  is  acute  and 
diffuse,  fever  may  be  present.  From  the  inconvenience  and 
suffering  which  diffuse  eczema  produces,  the  fever  and  loss  of 
albumin  to  the  body,  in  time  the  patient  becomes  anemic, 
emaciated,  and  cachectic. 

Horse. — In  the  horse  the  favorite  seats  of  eczema  are  the 
skin  of  the  bod}',  the  flexion  surfaces  of  the  hock,  fetlocks, 
and  the  mane  and  tail.  In  the  late  spring  and  summer  a 
rather  diffuse  papulovesicular  eczema  occurring  in  the  form 
of  nodules  and  scabs  appears  on  the  neck,  back,  sides  of  the 
shoulders,  and  croup.  This  is  thought  to  be  due  to  some 
"  disorder  of  the  blood,"  and  is  commonly  known  as  "  summer 
surfeit."  In  saddle  horses  in  the  saddle  rest  an  eczema 
occurs,  largely  induced  by  sweating  under  the  saddle  blanket. 
A  seborrheic  eczema  of  the  mane  and  tail  is  more  common 
than  suspected.  In  these  cases  the  proximal  ends  of  the  hairs 
are  embedded  in  and  matted  together  by  a  mass  of  fat,  fetid 
masses  of  exudate  and  sebmn,  over  which  large,  fish-scale- 
like, enlarged  epithelial  cells  are  found.  The  distal  end  of  the 
tail  is  most  frequently  invohed.  This  form  of  eczema  may 
lead  to  the  loss  of  the  tail  hairs  and  more  rarely  to  those  of 
the  mane.  In  old,  neglected  horses  out  of  condition  (bad 
teeth,  gastro-intestinal  catarrh)  a  generalized  squamous 
eczema  is  common.  Eczemas  of  the  limbs  to  which  are  given 
such  special  names  as  scratches,  mallenders,  etc.,  are  included 
in  works  on  surgery. 

Ox. — Eczema  is  not  so  common  in  cattle  as  in  the  horse, 
but  is  seen  to  occur  where  malt  or  potato  residue  is  fed.  It 
affects  principally  the  hind  limbs,  and  is  largely  due  to  the 
liquid  feces  which  come  in  contact  with  the  skin  of  the  legs. 
It  may,  however,  involve  the  fore  limbs,  the  body,  and  neck. 
This  eczema  is  vesicular  and  crustated.    It  usually  begins  with 


252  DISEASES  OF  THE  SKIN 

an  erythema,  the  skin  being  highly  reddened,  swollen,  and 
painful,  espeeially  about  the  hind  fetloeks.  The  ])atient  is 
usually  lame.  Later  there  appear  vesieles  which  soon  rup- 
ture, leaving  moist  areas  which  in  turn  dry,  forming  crusts. 
Tsually  the  eczema  tends  to  spread  on  the  limb  to  the  height 
of  the  carpus  or  tarsus.  The  patients  generally  show  s>in]> 
toms  of  loss  of  appetite,  diarrhea,  fever,  and  emaciation. 

Prognosis. — The  prognosis  is  usually  good,  healing  occurring 
in  about  three  weeks.  A  seborrheic  eczema  occasionally  is 
seen  in  cattle.  It  is  usually  diffuse  and  eventually  leads  to 
complete  loss  of  hair.  Dampness  is  a  common  cause  of 
eczema  in  sheep  which  have  been  exposed  to  continuous 
rainfall  which  keeps  the  wool  soaked.  The  eczema  is  usually 
found  along  the  back  and  croup.  This  form  of  eczema  is 
sometimes  called  "rain  rot."  The  skin  becomes  swollen  and 
creviced,  and  is  ciuite  itchy.  The  areas  involved  are  covered 
with  crusts  which  when  lifted  expose  moist  reddened  surfaces. 
The  wool  becomes  tufted  and  falls  out.  Pro^•ided  the  sheep 
are  not  removed  to  shelter,  they  become  anemic  and  emaci- 
ated. When  the  weather  gets  dry,  usually  the  eczema  sub- 
sides. 

Swine. — A  non-parasitic  eczema  is  rare  in  swine.  In  young, 
unthrifty  pigs  a  squamous  eczema  occurs  with  brown  or  black 
crusts,  hence  the  name  "soot  of  young  pigs."  This  form  of 
eczema  is  usually  seen  in  pigs  which  are  kept  in  unsanitary 
quarters  and  are  generally  neglected.  It  apjx'ars  })articular]y 
on  the  inner  surface  of  the  thighs  along  the  abdomen,  sides  of 
the  chest,  and  inner  surface  of  the  fore  limbs.  More  rarely 
it  affects  the  head.  The  affected  skin  is  erythematous  and 
soon  becomes  covered  with  vesicles  filled  with  a  clear,  sticky 
fluid.  Pustules  soon  form,  break,  dry,  and  form  crusts  which 
from  the  admixture  of  dirt  have  a  black  appearance.  Asso- 
ciated with  hog  cholera,  eczema  or  more  properly  an  exan- 
thema occurs. 

Treatment. — The  treatment  of  eczema  is  mainly  external. 
In  all  cases  the  cause  should  be  removed.  This  in  itself  often 
suffices.  Before  treatment  is  applied  the  affected  skin  should 
be  prepared  by  removing  the  hair  and  the  accumulations  of 
exudate.    For  the  latt(M',  bathing  the  skin  in  tepid  soft  water 


ECZEMA  253 

and  a  non-irritant  soap  followed  by  thorough  rinsing  and 
drying  are  important.  If  there  are  thick  scabs  or  crusts,  these 
may  be  softened  with  an  ointment  such  as  creolin  ointment. 

In  choosing  the  drugs  to  apply  it  must  be  borne  in  mind 
that  a  distinction  must  be  made  between  acute  and  chronic 
eczema . 

Acute  Eczema. — Water,  soap,  and  if  possible  air  should  be 
kept  from  the  affected  skin.  Crusts,  scabs,  and  secretions 
should  be  removed  with  Burrow's  solution  (5  per  cent.),  lime- 
water  and  oil  (equal  parts),  or  a  salicylic  acid  salve  (4  per 
cent.). 

When  the  skin  is  moist,  drying  powders  should  be  used. 

I^ — Amyl.  tritici giij 

Pulv.  alumini  silie 3v 

Zinci.  oxyd 3J 

M.  f.  strew  powder. 
or 

I^ — Zinci.  oxid.. 

Bismuth  subnitrici aa      3J 

Plumbi  carbonici gr.  xlv 

Pulv.  magnes.  silic giij 

M.  f.  strew  powder. 

Later  ointments  which  have  a  metallic  base  or  in  some 
instances  a  plant  base  may  be  used.  As  examples,  zinc  salve, 
lead  salve,  and  nitrate  of  silver  salve  (1  to  10).  Unna's  zinc 
paste : 

I^ — Oxidi.  zinci 10  parts 

Terra  silic 2      " 

Adeps  benzoat 28      " 

M.  f.  ungt. 

When  pruritus  is  marked  and  is  not  ameliorated  by  oint- 
ments a  silver  nitrate  solution  (10  per  cent.)  or  an  ichthyol 
salve  is  good. 

I^— Ichthj-ol, 
Zinci  oxid., 

Amyl.  tritici aa     1  part 

Vaselin 2     " 

M.  f.  ungt. 

In  very  moist  eczemas,  powders  are  more  valuable  than 
salves,  which  do  not  adhere  to  the  skin.     Powders  should  be 


254  DISEASES  OF   THE  SKIN 

applied  bountifully  two  or  three  times  daily,  the  old  powder 
removed  before  applying  the  new,  using  cotton  and  oil.  In 
obstinate  cases  nitrate  of  silver  (2  to  6  per  cent.)  or  picric 
acid  (1.5  per  cent.)  followed  by  powders,  and,  when  the 
exudate  is  dry,  by  salves. 

Chronic  Eczema. — Chronic  eczemas  are  treated,  contrary  to 
acute,  by  irritant  agents.  The  old  crusts  and  scales  should  be 
removed  with  Castile  soa])  and  soft  water  or  vaselin.  If  water 
is  used  the  skin  afterward  should  be  rubl^ed  perfectly  dry. 
If  the  skin  is  moist  from  exudate,  apply  jjowders,  as  in  acute 
eczema.  Later,  coal-tar  products  are  good,  such  as  tar  oint- 
ment (1  to  10)  or  tar  liniment: 

I^ — Pix  liquida  and  kaolin fifi      1  iiart 

Alcohol 5  to  10      " 

Creolin  preparations  are  also  indicated.  The  following 
prescription  has  been  found  useful : 

^ — Creolin gj 

Phenoli 5ss 

Florer's  sulph gj 

Spts.  terebinth.  5iv 

Liquor  animoni  ff)rtis giij 

Kerosene 5x1 

M.  f.  emulsio,  apply  with  brush. 

Nai)hthol  or  naphthalin  salve  (5  to  15  per  cent.)  or  iodin 
gylcerin  are  of  \'alue. 

I^ — Tint,  iodini 1  part 

Glycerin  4     " 

Salicylic  acid  ointment  (5  to  15  per  cent.)  and  pyrogallic 
acid  (5  to  15  per  cent.)  are  also  emi)loyed.  Pyrogallic  acid 
ointment  is  especially  useful  if  the  skin  is  much  thickened. 
All  of  these  agents  tend  to  loosen  the  crusts,  reduce  the  pruri- 
tus, and  assist  in  the  resori)tion  of  the  exudate. 

Internally  mild  cathartics  and  intestinal  disinfectants 
(calomel)  assist.  Fowler's  solution  of  arsenic  in  horses  is 
useful.  The  patient  should  be  given  good  care  and  food  and 
prevented  from  biting  or  scratching  the  parts. 


URTICARIA— NETTLE  RASH  255 

URTICARIA.     NETTLE  RASH. 

Definition. — Urticaria  is  an  eruption  of  the  skin  appearing 
in  the  form  of  rounded,  flattened  elevations,  which  appear 
and  disappear  suddenly,  due  to  an  infiltration  of  the  papillary 
bodies  and  the  ^Nlalpighian  layer  of  the  skin. 

Etiology. — Urticaria  is  common  in  horses,  cattle,  and  swine. 
The  causes  are  in  part  external  and  in  part  internal.  Urti- 
caria is  often  secondary  to  infectious  diseases. 

External  Causes. — The  external  causes  are  irritant  sub- 
stances, such  as  insect  stings,  chemical  agents  (turpentine), 
nettles,  and  rubbing  and  scratching  the  skin.  AVhen  the 
body  is  covered  with  sweat  and  suddenly  cooled  as  by  a 
shower  of  rain  m-ticaria  often  develops  in  horses. 

Internal  Causes. — Urticaria  is  very  often  a  s^^llptom  of 
digestive  distiu-bances,  gastro-intestinal  catarrh,  constipa- 
tion, and  so-called  indigestion,  or  of  general  infectious  dis- 
eases. There  is  probably  formed  in  these  cases  in  the  fer- 
menting ingesta  toxins  which  are  absorbed  and  irritate  the 
peripheral  bloodvessels.  Certain  foods  like  rye,  potato  tops, 
and  wheat  are  causes.  The  toxins  of  specific  microorganisms 
also  are  casual,  viz.,  dourine,  swine  erysipelas  ("diamond 
disease"'),  pm-pura,  influenza,  and  strangles.  Urticaria  also 
occurs  after  injections  with  tuberculin  or  mallein.  Cows 
which  have  gone  long  unmilked  sometimes  suffer  from  it. 
In  certain  mdividuals  there  is  an  idiosyncrasy  existing  favor- 
ing urticaria  when  certain  foods  are  eaten.  In  some  instances 
no  cause  can  be  determined. 

Symptoms.- — Usually  without  any  prodromal  s^•mptoms 
there  suddenly  appear  upon  the  skin  of  the  neck,  shoulder, 
sides  of  the  chest,  and  croup,  swellings  or  nodes  flattened  on 
top  and  varying  in  size  from  a  pea  to  a  clenched  fist  or  by 
confluence  even  larger.  The  hairs  over  the  swellings  are  dry 
and  stand  erect;  the  skin  between  is  normal.  In  some  in- 
stances vesicles  appear  on  the  swellings  which  erupt,  causing 
them  to  be  moist  or  covered  with  dry  exudate.  In  other 
instances  the  centres  of  the  nodes  sink,  leaving  a  wall-like 
periphery  (U.  annularis).  By  confluence  grotesque  figures 
may  appear. 


256  DISEASES  OF   THE  SKIN 

SimiJar  nodes  may  form  on  the  mueous  membranes  of  the 
nose  and  hirynx.  This  comphcation  may  lead  to  cough, 
dyspnea,  and  edema  of  the  glottis.  In  the  vagina  and  rectum 
they  may  induce  swelling  and  occasionally  prolapsus  recti. 
I'rticaria  may  also  involve  the  mouth  and  conjunctiva.  Con- 
comitant with  the  eruption  there  may  be  symptoms  of  general 
disturbance,  such  as  fever  and  loss  of  api)etite. 

Course. — Urticaria  usually  disappears  in  from  one  to  two 
days.  In  swine  it  may  take  from  four  to  six  days.  In  rare 
cases  so  much  serum  has  accunuilated  between  the  corium  and 
INIalpighian  layer  that  vesicles  api)ear  and  the  healing,  which 
takes  place  under  scab  formation,  is  prolonged.  Chronic 
cases  haA'e  been  noted,  occurring  with  frequent  relapses  and 
causing  the  condition  to  last  several  weeks  or  months.  Very 
rarely  death  results  from  edema  of  the  glottis. 

Treatment.^ — ^As  urticaria  usually  heals  spontaneousl\', 
treatment  is  rarely  necessary.  The  animal  should  be  placed 
on  short  rations  and  a  good  laxative  given.  Local  applica- 
tions to  the  skin  are  rarely  indicated. 

ALOPECIA. 

Definition. — By  alopecia  is  meant  a  falling  out  of  the  hairs 
without  apparent  skin  lesion,  and  not  due  to  parasites. 
Clinically  two  forms  of  alopecia  are  distinguished:  (a)  gen- 
eral alopecia  (A.  symptomatica)  and  {b)  local  alopecia 
(A.  areata). 

Etiology. — (a)  General  alopecia,  which  consists  in  the  hair 
falling  out  over  the  whole  body,  seems  to  be  due  to  some 
disturbance  in  the  nutrition  of  the  skin  with  atrophy  of  the 
hair  roots.  It  is  most  frequently  seen  to  follow  infectious 
diseases,  such  as  influenza,  jjurpura,  or  tetanus.  Toisoning 
with  mercury  and  lead  and  with  certain  foodstuffs  (potatoes) 
in  horses  are  causes.    Obesity  is  also  accused. 

(6)  Local  alopecia  is  probably  due  to  a  trophic  neurosis. 

Symptoms. — (Jeneral  al()])e('ia  usually  affects  the  whole 
body,  the  mane  and  tail  being  the  last  to  fall  out.  The  hair 
coat  gradually  grows  thinner  and  thinner  until  it  <lisapi)ears 
except  in  a  few  places   where   it  is  usually  retained.     The 


PRURITUS  257 

loss  of  hair  is  often  only  temporary,  the  denuded  skin  soon 
again  becoming  covered  with  fine  downy  hair  which  grows  out 
to  full  length.  Local  alopecia  appears  in  the  form  of  small, 
round  bald  areas  which  gradually  increase  in  size  and  by 
coalescence  form  large  bald  spots.  The  skin  is  intact,  al- 
though, as  a  rule,  it  is  darker  in  color  than  normal. 

Diagnosis. — Alopecia  might  be  confused  with  herpes  ton- 
surans or  with  mange.  However,  the  absence  of  scales  and 
broken  hair  shafts  differentiate  it  from  the  former;  the 
eczema  and  presence  of  the  mange  mite  suffice  to  distinguish 
mange  from  it. 

Treatment. — \Nhi\e  general  alopecia  usually  leaves  of  itself 
in  a  few  weeks,  provided  the  patient  and  skin  are  given  good 
care,  the  local  form  is  often  quite  obstinate  and  frequently 
incurable.  Fluids  containing  alcohol  and  some  irritant  are 
generally  recommended.  Tincture  of  cantharides  (1  to  o 
alcohol)',  tincture  of  iodin  (1  to  1  to  5  alcohol),  and  creolin 
(1  to  10  to  20  alcohol)  are  examples. 

ERYTHEMA. 

Definition.— Erythema  is  an  inflammatory  congestion  of 
the  skin  which  may  be  primary  and  result  from  various 
mechanical,  chemical,  and  thermic  causes;  it  may  be  a  s^•^llp- 
tom  of  eczema,  or  it  occurs  secondary  to  infections  and  intoxi- 
cations. In  hog  cholera,  erythema  is  occasionally  seen;  in 
swine  erysipelas  it  is  a  constant  symptom.  White  swine  and 
sheep  are  affected  by  it  if  they  eat  growing  buckwheat  in  the 
bright  sunlight. 

PRURITUS. 

Definition. — By  pruritus  an  itching  of  the  skin  without 
visible  lesion  is  meant.    It  may  be  local  or  general. 

Etiology. — The  causes  are  not  well  understood.  In  some  of 
the  infectious  diseases,  such  as  rabies,  dourine,  and  in  dis- 
orders due  to  worms  like  trichinosis  and  grub-in-the-head  of 
sheep,  it  has  been  observed.  Severe  general  diseases  are  some- 
times accompanied  b>-  pruritus,  such  as  chronic  nephritis, 
icterus,  and  diabetes  mellitis. 
17 


258  DISEASES  OF  THE  SKIN 

Treatment. — Treatment  is  usually  of  little  avail,  and  con- 
sists in  the  application  of  local  anesthetics  or  irritants. 

TRICHORRHEXIS  NODOSA. 

Definition. — This  is  a  condition  of  the  hair  in  which  nodules 
occur  along  the  shaft,  causing  the  hair  to  bend  and  break  off. 

It  may  affect  the  hairs  of  the  body  or  the  mane  and  tail  of 
the  horse.  As  it  sometimes  occurs  enzootically  it  is  probably 
due  to  an  infection  of  the  hair.  It  may  be  transmitted  from 
one  animal  to  another  or  to  man. 

Prognosis. — The  prognosis  is  unfavorable. 

Treatment. — The  treatment  consists  in  the  application  of 
antiseptics,  such  as  bichlorid  of  mercury  (1  per  cent.), 
creolin  (2  per  cent.),  pyrogallol  (1  per  cent.),  or  pyoctanin 
(1  per  cent.). 

ACNE. 

Definition. — By  acne  is  meant  a  purulent  inflammation  of 
the  hair  follicles.  There  form  on  the  skin,  papules  and  ])us- 
tules.  It  is  due  to  an  infection  with  pus  cocci  and  the  result- 
ing decomposition  of  the  sebum.  A  parasitic  form  which  is 
rare  in  large  animals  is  due  to  the  mite  Demodex  folliculorum. 

In  horses  acne  usually  occurs  in  the  saddle  or  harness 
rests  where  firm,  painful  nodules  or  nodes  appear  out  of  which 
may  be  expressed  in  the  form  of  yellow  waxy  cylinders  an 
exudate  which  is  a  mixture  of  sebum  and  pus. 

Treatment. — The  treatment  is  surgical,  and  consists  in  open- 
ing, expressing  the  exudate,  and  curetting  out  the  ca\ity, 
which  is  later  cauterized. 

PEMPHIGUS. 

Definition. — By  pemphigus  is  understood  a  skin  eruption 
characterized  by  isolated  vesicles,  which  may  attain  the  size 
of  a  hen's  egg  or  e\en  larger,  between  which  the  skin  appears 
intact. 

Etiology. — The  causes  are  not  known. 

Prognosis. — In  animals  the  prognosis  is  good,  most  cases 
healing  in  about  two  weeks. 


SCABIES— MANGE— SCAB  259 

SCABIES.     MANGE.     SCAB. 

Definition. — Scabies  is  an  eczema  produced  by  minute 
insects  and  attended  by  intense  itching. 

Occurrence. — As  scabies  is  contagious  it  assumes  at  times 
an  enzootic  or  even  epizootic  distribution.  Particularly  is 
this  true  of  the  scabies  of  sheep,  which  in  a  single  state  may 
affect  thousands  of  animals  and  lead  to  great  economic 
losses. 

Etiology. — Scabies  is  caused  by  a  small  spider-like  mite 
which  can  rarely  be  seen  with  the  naked  eye,  the  mites 
belonging  to  the  order  acarina,  class  arachnoidea.  They 
are  from  0.2  to  0.8  mm.  in  size,  provided  with  four  pairs  of 
legs  and  an  undivided  trunk.  The  males  are  smaller  than  the 
females.  The  females  lay  eggs  which  in  about  eight  days 
hatch  six-legged  larvse.  In  eight  days  the  larva?  become  sex- 
ually mature.  The  females  live  for  three  to  five  weeks,  the 
males  about  six  weeks.  Under  favorable  circumstances  mites 
may  live  as  long  as  eight  weeks,  and  under  contrary  condi- 
tions as  short  a  time  as  two  weeks.  Infestation  may  be  from 
direct  contact  or  through  intermediary  agents,  such  as  har- 
ness, grooming  utensils,  blankets,  bedding,  etc. 

Varieties. — Three  varieties  of  mites  are  distinguished:  (a) 
Sarcoptes,  (b)  Psoroptes,  and  (c)  Symbiotes.  A  fourth 
species,  the  follicle  mite,  is  usually  not  included  under  the 
mange  mites. 

Sarcoptes  Mite. — This  is  a  burrowing  parasite  which  lives 
in  the  Malpighian  layer  of  the  skin  where  it  forms  tunnels 
imder  the  epidermis.  It  is  the  smallest  species  (0.2  to  0.5 
mm.),  shaped  like  a  turtle,  with  a  head  like  a  horseshoe  and 
\'ery  short  legs.  Three  varieties  of  sarcoptes  occur  in  animals : 
(a)  Sarcoptes  scabei  of  the  horse,  (h)  Sarcoptes  squamiferus 
of  the  dog,  and  (c)  Sarcoptes  minor  of  the  cat. 

Psoroptes,  or  Sucking  Mite. — This  minute  insect  lives 
upon  the  surface  of  the  skin,  and  is  nourished  by  the  blood 
and  lymph.  It  is  the  largest  of  the  mites  (0.5  to  0.8),  and 
under  favorable  circumstances  (on  black  paper,  for  instance) 
may  be  seen  with  the  naked  eye.  Its  head  is  pointed,  legs 
very  long,  and  feet  provided  with  tulip-shaped  suckers.    Two 


2(i()  DISEASES  OF   THE  SKIN 

varieties  of  this  mite  occur  in  animals:  (a)  Psoroptes  com- 
munis of  the  sheep,  and  horse  and  more  rarely  in  cattle  and 
buffalo,  (b)  the  Psoroptes  caniculi  of  rabbits. 

Symhiotes  or  Scale-eating  Mite. — This  mite  lixes  on  the 
surface  of  the  skin  and  on  scales  of  epithelium.  In  size  it 
stands  between  the  Sarcoptes  and  the  Psoroptes  (0.3  to  0.5 
mm.).  The  head  is  short,  blunt,  almost  round,  and  the  legs 
long,  provided  with  suckers.  Two  varieties  belong  to  this 
species:  (a)  S\inbiotes  communis  of  horses  and  cattle,  and 
(6)  Symhiotes  felis,  canis,  and  cuniculi  (cat,  dog,  rabbit). 

Mange  of  the  Horse. — Forms. — On  the  skin  of  the  horse 
all  three  forms  of  mange  mites  appear. 

Sarcoptic  Mange. —  Definition. — This  is  the  most  important 
form  of  mange  of  the  horse.  It  attacks  the  skin  of  the  body, 
neck,  and  head,  and  can  become  general. 

Symptoms. — The  s\Tnptoms  are  those  of  eczema  (papules, 
vesicles,  crusts),  accompanied  liy  severe  itching,  which  causes 
the  animal  to  rub,  bite,  and  scratch  itself,  especially  during 
warm  nights.  It  leads  to  alopecia,  thickening,  folding  of  the 
skin,  and  in  time  to  emaciation.  Characteristic  of  mange  is 
the  tendency  for  the  eczema  to  spread  and  the  transmissibility 
to  other  horses  and  even  to  man. 

Diagnosis. — A  positive  diagnosis  can  be  made  only  with 
the  microscope.  As  the  mites  are  in  tunnels  under  the 
epidermis  the  scraping  should  be  made  deep  enough  to  reach 
them,  and  as  a  number  of  mites  found  are  generally  limited, 
several  slides  should  be  examined  before  an  opinion  is 
given. 

Prognosis. — In  this  form  of  mange  the  ])rognosis  is  always 
doubtful,  for  unless  circumscribed  it  may  take  several  weeks 
or  months  of  persistent  treatment  to  eradicate  the  mites. 

Treatment. — Success  in  treating  sarcoptes  mange  lies  not  so 
much  in  the  agent  used  as  it  does  in  the  thoroughness  and 
persistency  in  the  application.  The  following  agents  are 
recommended:  Creolin  (3  per  cent.),  creolin  salve  (I  to  25), 
and  creolin  liniment,  which  consists  of: 


I^ — Creolini  et  sapoii  viridi afi      5>v 

Alcohol Oj 


SCABIES— MANGE— SCAB  261 

Tar  liniment : 

I^ — Fix's  liquicla  et  flores  sulph aa      5xvj 

Sapon  viridi  and  alcohol «    aa      Oij 

As  further  agents  may  be  mentioned  tobacco  decoction 
(5  per  cent.)  and  sulphur  salve: 

I^ — Flores  sulph 5iij 

Potassii  carbon oiiss 

Adipis  suill Biij 

Besides  the  treatment  of  the  patient  it  is  always  advisable 
to  thoroughly  disinfect  the  stable,  stable  utensils,  harness, 
etc.,  which  may  reinfest. 

Psoroptic  Mange. — This  form  of  mange  occurs  in  the 
most  protected  parts  of  the  body,  such  as  the  mane,  tail, 
sheath,  medial  surface  of  the  hind  limbs,  region  of  the  throat, 
etc.  It  may,  however,  spread  over  the  whole  body  thus, 
resembling  sarcoptes  mange. 

Diagnosis. — ^The  diagnosis  is  made  with  the  microscope. 

Prognosis. — The  prognosis  is  more  favorable  in  this  than 
in  the  sarcoptes  form,  as  the  mites  are  on  the  surface.  How- 
ever, especiall}^  in  cold  weather,  which  interferes  with  the 
application  of  the  treatment,  the  case  may  prove  obstinate. 

Treatment. — Treatment  is  the  same  as  for  sarcoptic  mange. 

Symbiotic  Mange. — This  form  occurs  about  the  fetlocks, 
especially  under  the  flexion  of  the  joint. 

Symptoms. — The  symptoms  are  similar  to  those  of  scratches 
(squamous  and  crustated  eczema),  but  the  affected  parts  are 
itchy,  causing  the  animal  to  gnaw  them  and  stamp  its  feet. 
At  times  the  lesions  may  extend  up  the  leg  to  the  tarsal  or 
carpal  joints,  but  rarely  higher. 

Diagnosis. — ^The  diagnosis  is  made  with  the  microscope. 

Prognosis. — Prognosis  is  favorable. 

Treatment. — Usually  a  creolin  salve  or  a  tar  salve  suffices 
to  produce  a  cure. 

Sheep  Scab. — Mange  of  Sheep. — The  most  common  form 
of  mange  in  sheep,  so-called  sheep  scab,  is  psoroptic  mange. 
However,  the  sarcoptic  and  symbiotic  mites  also  attack 
sheep. 


262  DISEASES  OF   THE  SKIX 

Psoroptic  Mange. — Occurrence. — This  form  of  inanije  or 
scab  is  widely  i)revaleiit  in  the  rnited  States.  Throuj^h  the 
efforts  of  the  Bureau  of  Animal  Industry,  with  the  coopera- 
tion of  the  great  sheep-grazing  States  (Colorado,  ^Fontana, 
Wyoming),  sheep  scab  has  been  greatly  reduced  in  the  past 
few  years. 

SymjJtoms. — Psoroptic  mange  affects  the  parts  of  the 
skin  which  are  covered  with  wool.  It  therefore  usually 
appears  in  the  shoulder  region,  along  the  back,  cronj),  sides 
of  the  chest  and  neck.  It  does  not  involve  the  ventral  chest 
or  abdominal  regions. 

The  first  symptoms  noted  are  usually  those  of  itchiness. 
The  sheep  are  uneasy,  bite  and  rub  the  afi'ected  skin.  The 
wool  soon  becomes  loose  and  tufted.  The  itchiness  is  most 
noticeable  in  hot  weather,  after  exercise,  in  warm  stables  and 
at  night.  If  the  wool  is  separated  and  the  skin  examined  red 
or  yellowish  papules  the  size  of  a  hemp  seed  are  noted; 
eventually  vesicles  or  pustules,  as  well  as  thin,  yellowish, 
fatty  crusts  and  scabs,  ap])ear.  By  confluence  large  irregular 
areas  are  formed,  covered  with  thick  yellow  crusts.  The 
crusts  or  scales  adhere  to  the  w^ool  and  by  its  growth  are 
elevated  from  the  underlying  skin.  The  wool  soon  becomes 
tufted  and  the  surface  of  the  fleece  uneven;  or  it  falls  out, 
leaving  bald  areas,  especially  along  the  back  and  sides.  In 
shorn  sheep  or  on  the  bald  areas  the  scales  are  dry  and  brown 
in  color.  The  disease  develops  rapidly  under  the  fleece, 
especially  in  stables,  so  that  in  six  to  eight  weeks  the  whole 
body  may  be  denuded  of  wool.  When  the  whole  trunk  is 
involved  on  account  of  the  loss  of  albumin,  unrest,  and  inter- 
ference with  feeding,  the  weaker  sheep  become  anemic,  emaci- 
ated, cachectic,  and  often  die.  This  is  especially  true  in 
winter  when  the  sheep  are  stabled.  After  shearing  and  turn- 
ing out  on  grass  temporary  improvement  is  noted. 

Diagnosis. — The  diagnosis  depends  upon  finding  the  mites 
by  scraping  freshly  infected  areas  where  the  scabs  are  soft, 
placing  the  scra})ing  on  a  piece  of  black  ])a])cr  in  the  sun  and 
with  a  hand  lens  noting  the  minute  mites  which  are  seen 
crawling  toward  the  edge  of  the  paper.  Obviously  a  better 
view  may  be  obtained  through  the  microscope.    In  ^•ery  old 


SCABIES— MANGE— SCAB  263 

cases  (scabs  hard  ami  dry)  or  if  dips  have  been  used  the  mites 
are  not  numerous. 

Prognosis. — ^The  prognosis  in  sheep  scab  is  generally  good, 
provided  prompt  and  effective  remedial  measures  are  taken. 

Treatment. — The  treatment  consists  in  dipping  the  whole 
flock  in  some  solution  which  will  destroy  the  parasites. 
Several  solutions  are  recommended  for  this  puropse: 

(fl)  Lime-sulphur  dip,  made  bj'  mixing  eight  pounds  of 
fresh  quicklime  and  twenty-four  pounds  of  sulphur  and  boil- 
ing with  thirty  gallons  of  water  for  not  less  than  two  hours. 
All  sediment  should  be  allowed  to  subside  before  the  liquid 
is  placed  in  the  dipping  vat.  Before  using  this  mixture  it 
should  be  diluted  with  water  to  make  100  gallons. 

(b)  Tobacco-sulphur  dip  which  is  made  with  the  extract 
of  tobacco  or  nicotin.  The  strength  of  the  mixture  should  be 
not  less  than  0.05  per  cent,  nicotin  and  2  per  cent,  flowers  of 
sulphur.  For  the  first  dipping  of  infected  sheep  the  mixture 
should  contain  no  less  than  0.07  per  cent,  nicotin. 

(c)  Coal-tar  preparation  to  50  to  75  parts  water.  Dipping 
solutions  should  be  warm  (110°  F.). 

Sheep  should  be  immersed  at  least  once  and  should  remain 
in  the  solution  for  at  least  two  minutes.  It  is  best  to  dip 
after  shearing.  Ten  days  later  the  entire  flock  should  be 
dipped  a  second  time.  After  dipping  the  flock  should  be 
placed  where  no  scabby  sheep  have  been  for  at  least  four  or 
five  weeks. 

Sarcoptic  Mange  of  Sheep. — As  this  form  of  mange  does  not 
usually  invade  the  wool-covered  portions  of  the  skin  it  is 
found  mostly  on  the  head  about  the  lips,  nose,  face  and  ears. 
It  is  therefore  known  as  "head  mange."  More  rarely  it 
involves  the  flexion  surfaces  of  the  carpi  and  tarsi. 

Symptoms. — The  symptoms  are  similar  to  those  noted  in 
the  horse.  Small  papules,  vesicles,  and  pustules  appear  which 
rupture  and  dry  to  form  thin  and  later  thick  gray  scabs; 
from  rubbing  the  skin  becomes  swollen  and  creviced. 

Prognosis. — The  prognosis  is  good  if  treated  early.  In 
some  cases  the  sheep  are  unable  to  eat. 

Treatment. — ^Treatment  is  the  same  as  for  sarcoptic  mange 
in  the  horse. 


204  DISEASES  OF  THE  SKIN 

Symbiotic  Mange  in  Sheep. — Symbiotic  mange  is  very  rare 
in  sheep  and  a])i)ears  around  tlie  fetlocks  and  coronets, 
usually  of  the  hind  feet.  Besides  an  ec/.ematous  eru])tion 
there  is  pruritus,  causing  restlessness  and  stamping.  In 
rare  instances  the  scrotum  or  udder  may  be  attacked. 
Healing  usually  occurs  spontaneously  when  the  sheep  are 
turned  out  on  grass. 

Cattle  Mange. — In  the  ox  the  ])rincipal  mange  is  the 
psoroptic.  The  fa^•orite  seats  are  the  lateral  surfaces  and 
crest  of  the  neck,  base  of  the  horns,  withers  and  root  of 
the  tail.     It  rarely  appears  over  the  whole  body. 

Symptoms.  The  symptoms  are  those  of  pruritus  and  the 
appearance  on  the  skin  of  brownish-gray  crusts  and  scabs, 
the  skin  becoming  thickened  and  welted.  The  hair  falls  out 
over  the  infested  regions.  Excoriations  of  the  skin  may  be 
caused  by  the  ])atient  rubbing  the  part.  If  generalized  the 
patient  becomes  anemic,  emaciated,  cachectic  and  often  dies 
of  inanition.  The  disease  is  worse  in  w^inter  when  the  cattle 
are  stabled  but  improves  in  the  spring  when  they  are  turned 
out  to  graze. 

Treatment. — 'JVeatment  is  the  same  as  for  horse  mange, 
avoiding,  however,  a])i)lications  which  contain  mercury. 

Symbiotic  Mange.  This  form  occurs  at  the  tail  root, 
on  each  side  of  the  anus,  and  also  on  the  legs.  In  rare  in- 
stances it  may  ai)i)ear  over  the  crou]),  loins,  back,  side  of  the 
thigh  and  udder.  It  is  characterized  by  pruritus,  scabs, 
squama'  and  loss  of  hair.  It  usually  does  not  affect  the 
animal  seriously  but  is  worse  during  winter  than  in  summer. 

Trcatvienf.- — Treatment  is  the  same  as  for  psoroptic 
mange. 

Mange  of  Swine. — In  swine  the  only  mange  is  the  sarcoptic. 
This  is  not  a  connnon  skin  disease  in  America.  The  favorite 
seats  are  about  the  head  (eyes,  cheeks,  ears),  although  it  may 
extend  from  these  ])arts  to  the  neck,  trunk,  and  limbs. 

Symptoms. — The  symptoms  are  those  of  seNcre  itching, 
with  which  is  associated  a  squamous  eczema,  the  skin  being 
covered  with  bran-like  scales  which  accumulate  to  form  thick 
crusts.  If  diifuse  the  skin  surface  assumes  a  peculiar  silvered 
appearance  "as  if  strewn  with  guano."    The  underlying  skin 


HERPES— RINGWORM  265 

is  thickened  and  creviced.  If  diffuse  and  of  long  duration 
emaciation  follows.  It  is  difficult  to  find  the  mites  under  the 
microsco])e,  as  they  are  limited  in  numbers. 

Treatment. — The  skin  should  be  thoroughly  scrubbed  with 
green  soap  and  water  to  soften  the  crusts.  This  may  be 
followed  by  the  use  of  sulphur  ointment,  creolin  liniment,  or 
a  tar  salve. 

Follicular  Mange. — Occurrence. — This  form  of  mange, 
which  is  common  in  dogs,  where  it  assumes  two  forms, 
the  squamous  and  the  pustular,  is  rare  in  other  animals,  with 
the  possible  exception  of  the  pig. 

Etiology. — The  hair  follicle  mites,  Acarus  folliculorum,  live 
in  the  sebaceous  glands  and  hair  follicles.  Following  their 
invasion  pus  cocci  enter,  leading  to  abscess  formation.  In 
swine  the  Demodex  folliculorum  (var.  suis)  is  the  offender. 
The  region  of  the  snout,  neck,  ventral  portion  of  the  chest, 
the  abdomen  and  inner  parts  of  the  thighs  are  the  favorite 
seats.  In  these  regions  pox-like  pustules  to  hazel-nut-sized 
boils  or  abscesses  as  large  as  walnuts  appear.  In  the  centre 
of  an  abscess  hundreds  of  the  mites  may  be  found. 

Diagnosis. — Diagnosis  depends  upon  finding  the  mites 
under  the  microscope. 

Prognosis. — The  prognosis  in  swine  is  not  good,  as  the  dis- 
ease is  very  obstinate.  An  operative  treatment  which  con- 
sists in  removing  the  affected  skin  is  recommended. 


HERPES.     RINGWORM. 

Definition. — A  contagious  skin  disease  due  to  a  fungus  and 
characterized  by  the  formation  of  round,  sharply  defined 
areas  covered  with  scales  and  short  uneven  hair  stumps. 

Occurrence. — Ringworm  is  very  common  in  cattle,  especially 
during  the  winter  season,  when  they  are  stabled.  It  is  some- 
times, therefore,  known  as  "barn  itch."  While  more  or 
less  troublesome  it  is  a  benign  disease.  Horses  are  also 
affected  with  it,  as  are  sheep  and  pigs. 

Etioloyg. — Ringworm  is  caused  by  the  fungus  Trichophyton 
tonsurans.     This  fungus  is  made  up  of   threads    (hyphse) 


200  DISEASES  OF   THE  SKIN 

which  are  intenvoven  to  form  mycelia  and  hirf;;e,  round,  light- 
ri'fra('tiii<j;  spores  whieli  predominate.  'I'he  funijus  li\es  in 
the  hair  sac,  where  it  ])ro(hices  an  iiiflannnation  of  the  hair 
folUcle,  causing  the  hair  to  fall  out,  and  also  within  the  iiair 
shaft,  which  it  makes  brittle,  causing  it  to  break  off.  In- 
fection is  spread  by  direct  contact  or  through  intermediary 
agents,  such  as  posts,  stall  partitions,  etc.,  against  which 
afl'ected  animals  have  rubbed  themselves.  Harness,  saddles, 
and  grooming  utensils  are  also  carriers. 

Forms. — Four  forms  of  herpes  tonsurans  are  distinguished 
clinically,  depending  upon  the  species  of  animals  attacked  and 
the  location  and  age  of  the  lesion:  (a)  Herpes  tonsurans 
which  is  characterized  by  round  bald  spots  w^ithout  inflam- 
mation of  the  skin. 

(b)  Herpes  circinatus,  the  centre  healing  but  the  peripherj- 
remaining  diseased  thus  forming  a  hoop-shaped,  circular 
lesion — hence  the  name  "ringworm."  (c)  Herpes  maculosis, 
occurring  on  the  skin  of  old  animals  and  leading  to  alopecia 
and  a  superficial  chronic  dermatitis  with  desquamation  of 
the  epidermis  which  forms  slate-gray-colored,  asbestos-like 
scales,  (d)  Herpes  vesiculosus  which  attacks  the  thin  skin  of 
young  animals  (calves,  lambs).  This  is  a  dermatitis  with 
^•esicle  formation.  The  vesicles  soon  rupture  forming  thick 
yellow  scaly  scabs  or  crusts  in  the  neighborhood  of  the  mouth, 
face  and  eyes. 

Cattle. — In  adult  cattle  herpes  usually  attacks  first  the 
head  and  neck,  where  it  forms  small,  well-defined,  round  bald 
spots  which  by  confluence  may  reach  the  size  of  an  open 
hand.  These  areas  are  co^•ered  with  grayish-white,  asbestos- 
like crusts.  On  black  skin  the  crusts  are  thicker  than  on 
white.  The  skin  is  sometimes  thickened  and  creviced. 
Healing  usually  takes  place  imder  the  crusts  in  two  or  three 
months.  When  there  is  much  pruritus,  causing  rubbing  and 
scratching,  secondary  lesions  form,  i)r()longing  the  course  of 
the  disease  several  months. 

Diagnosis. — A  positive  diagnosis  can  be  made  only  with  the 
microscope.  In  sucking  calves  herpes  attacks  the  skin  around 
the  mouth.  There  a])i)ear  round  spots  covered  with  yellowish 
scabs  made  up  of  ])ran-like  scales. 


CONTAGIOUS  PUSTULOUS  DERMATITIS  267 

Horses. — The  favorite  seat  of  herpes  in  the  horse  is  the 
head,  back,  shoulders,  and  croup.  As  a  rule  it  assumes  the 
form  of  round,  well-defined  bald  spots  the  size  of  a  25-cent 
piece.  Usually  there  is  no  pruritus.  In  rare  instances  a 
Herpes  vesiculosus  occurs  on  the  sheath  and  inner  surface  of 
the  hind  limbs,  with  the  formation  of  scabs  and  crusts. 

Treatment. — The  treatment  depends  somewhat  on  the  ex- 
tent and  form  of  the  eruption.  When  feasible  it  is  advisable 
to  shear  off  the  hair  and  soften  up  the  crusts  with  green  soap. 
This  may  be  followed  by  painting  the  areas  with  tincture  of 
iodin  or  salicylic  acid  in  alcohol  (1  to  10).  In  horses  mercuric 
ointment  is  useful.  In  obstinate  cases  nitric  acid  may  be 
tried.  However,  most  cases  yield  to  treatment  with  any 
disinfectant.  One  attack  of  herpes  produces  a  certain  im- 
munity against  subsequent  ones. 

FAVUS. 

Favus  is  a  contagious  skin  disease  common  in  man  but 
very  rare  in  animals,  caused  by  a  fungus  similar  to  the  Tricho- 
phyton tonsurans  and  called  the  Achorion  Schoenleinii.  It 
forms  round,  thick  sc.abs  on  the  skin  which  being  depressed 
in  their  centres  are  saucer-  or  shield-shaped.  The  scabs  have 
a  sulphur-yellow  color,  especially  toward  the  centre.  They 
appear  upon  the  head,  abdomen,  and  feet  of  carnivora.  In 
fowls  the  comb  and  wattles  are  the  favorite  seats.  The  treat- 
ment is  the  same  as  for  herpes. 

CONTAGIOUS  PUSTULOUS  DERMATITIS.     CONTAGIOUS 

ACNE. 

Definition. — Contagious  pustulous  dermatitis  is  a  benign 
pustular  exanthema  of  horses  which  occurs  in  the  regions  of 
the  harness  and  saddle  rests. 

Etiology. — The  disease  is  not  very  common,  but  occurs 
occasionally  enzootically.  The  pustules  are  caused  by  the 
acne  bacillus.  Infection  takes  place  usually  through  inter- 
mediary agents  such  as  harness  and  saddles. 

Symptoms. — In  the  region  noted  round  or  oval  swellings 
the  size  of  a  25-cent  piece  appear,  which  in  a  day  or  so 


2G8  DISEASES  OF   THE  SKIN 

become  covered  with  small  hempseed-sized  vesicles,  Avhicli 
rapidly  form  ])iistiiK's.  The  pustules  usually  break  in  twenty- 
four  to  thirty-six  hours,  forming  thick,  yellow,  sticky  crusts 
which  heal  in  about  two  weeks.  There  is  usually  little  or  no 
])ruritus.  In  severe  cases  boils  or  cNcn  abscesses  may  form 
as  in  simple  acne.  The  abscesses  may  rupture,  formino; 
ulcers  which  heal  vmder  the  scab.  In  rare  instances  an  in- 
flammation of  the  lymph  vessels  and  glands  complicate  the 
case.  Healing  in  these  cases  requires  one  or  two  months. 
This  form  of  contagious  pustulous  dermatitis  may  resemble 
skin  glanders.  However,  even  in  the  most  severe  cases  there 
are  no  general  symptoms. 

Diagnosis. — The  location,  absence  of  itching  and  contagious 
character  differentiate  contagious  jmstulous  dermatitis  from 
acne  or  other  suppurati\e  conditions  of  the  skin  due  to 
tramnatism. 

Treatment. — The  patient  should  not  be  worked,  the  sick 
isolated  from  the  healthy,  and  the  pustules  opened  and 
treated  with  antiseptics.  The  harness,  saddle,  and  stable 
should  be  disinfected. 


HYPODERMA  LINEATUM.     WARBLE  FLIES. 

The  cattle  bot,  or  warble  fly,  one  \ariety  of  which  appears 
in  the  United  States,  produces  serious  discomfort  to  cattle 
and  damage  to  hides,  due  t<j^  the  perforations  which  they 
cause  in  the  skin  of  the  shoulder,  back,  and  breast. 

Life  History. — The  female  gadfly  de])osits  her  eggs  in 
sunnner,  while  the  cattle  are  on  pasture,  on  the  legs,  tail  and 
body  where  they  are  licked  ofl'  by  the  animal,  reaching  the 
mouth  and  throat  where  they  hatch.  The  larva'  perforate 
the  gullet  and,  following  the  course  of  the  bloodvessels  in 
the  mediastinal  tissue,  reach  the  vertebral  foraminje,  through 
which  they  pass  into  the  vertebral  canal,  eventually  emigrat- 
ing to  the  subcutaneous  tissue  of  the  back.  In  the  subcutis 
they  become  encapsuled  in  a  sac  of  connective  tissue,  forming 
pigeon-egg-sized  enlargements  which  are  called  warbles. 
When  fully  developed  the  following  spring  they  perforate  the 


LICE  2G9 

skin,  pass  out  through  the  openings,  drop  to  the  ground,  into 
which  they  burrow  and  pupate,  finally  emerging  as  adult 
flies.  As  many  as  50  to  100  of  these  larva?  may  perforate 
the  skin,  causing  the  hide,  which  is  called  "grubby,"  to  be 
docked  one-third  in  value  on  the  market.  Occasionally  they 
may  produce  emaciation. 

Treatment. — The  treatment  consists  in  applying  turpentine 
to  the  opening  over  the  warble.  Those  not  killed  by  this 
method  may  be  pressed  out  by  hand  and  destroyed. 

Prevention. — Applying  various  disinfectants  to  the  backs  of 
cattle  is  of  no  value  from  a  prophylactic  standpoint. 


LICE. 

Definition. — Lice  are  blood-sucking  parasites  (h?emato- 
pinus).  Each  one  of  the  domesticated  animals  harbors  its 
own  species.  They  are  frequently  found  on  cattle  (Hsema- 
topinus  eurysternus)  and  horses  (Hsematopinus  equi) .  How- 
ever, occasionally  lice  will  pass  from  one  host  to  another  of  a 
different  species.  Chicken  lice,  for  instance,  will  attack 
horses  and  human  beings.  Lice  are  very  prolific.  It  is  said 
that  a  single  pair  may  produce  in  three  months  125,000 
individuals.  Lice  produce  itching,  loss  of  hair,  and  give  the 
animal  an  unthrifty  app'earance.  While  they  may  be  found 
on  any  part  of  the  body  they  first  appear  about  the  neck. 
As  they  are  large  enough  to  be^seen  by  the  naked  eye,  if  the 
light  is  good,  the  diagnosis  is  usually  easy.  Even  the  eggs 
or  nits  are  visible  as  small  ovoid  bodies  attached  to  the  hairs. 

Treatment. — Several  remedies  will  kill  lice.  For  horses  one 
of  the  most  valuable  is  gray  mercurial  ointment.  Creolin 
(2  per  cent.)  is  also  good.  An  infusion  of  tobacco  made  by 
boiling  tobacco  (5iij)  in  water  (Oij)  is  recommended.  A 
great  favorite  is  kerosene  emulsion,  made  by  dissolving  soft 
soap  (Oij)  in  boiling  water  (Oij)  and  adding  kerosene  (Oj). 
This  mixture  should  be  churned  or  stirred  violently  and  3 
quarts  of  water  added  to  it  before  using.  Pure  kerosene  is 
too  strong  and  causes  loss  of  hair.  Stavesacre  seeds  (§ij) 
boiled  in  water  (Oij)  is  an  efficient  agent  to  destroy  lice. 


270  DISEASES  OF   THE  SKIN 

TICKS.     IXODOIDEA. 

Definition. — Ticks  are  skin  ])arasites  wliicli,  however,  do 
not  remain  parasitic  throughout  life.  The  females  especially 
attach  themselves  to  the  skin  into  which  they  bore.  The  most 
important  tick  is  the  Texas  cattle  tick  (Margaropus  annu- 
latus)  which  transmits  the  germ  of  Texas  fever.  While 
common  on  cattle  in  the  Southern  States  it  is  only  an  occa- 
sional visitor  in  the  North,  where  it  is  unable  to  withstand 
the  cold  winter.  Ixodes  reduvius,  which  is  parasitic  on  sheej) 
and  cattle,  is  not  uncommon.  The  same  treatment  recom- 
mended for  lice  will  destroy  ticks.  (For  eradication  of  the 
Texas  fever  tick  see  Texas  Fever.) 

THE  SCREW  FLY. 

The  screw  fly  (Compsomyia  macellaria)  is  a  small,  bluish- 
green  fly  with  a  brown  head  and  three  black  longitudinal 
stripes  on  the  thorax.  The  female  deposits  her  eggs  in 
wounds,  where  they  hatch  in  a  few  hours  (larvte,  maggots), 
the  maggots  burrowing  into  the  tissue,  where  they  remain  for 
a  week.  They  then  escape  from  the  wound,  reach  the  ground, 
pu])ate,  and  change  to  adult  flies.  In  some  regions  of  the 
South  they  are  very  troublesome,  infesting  the  smallest 
wounds  and  causing  serious  losses. 

Treatment. — Pure  creolin  should  be  injected  into  the 
wound.     Fresh  wounds  can  be  protected  by  a  tar  covering. 

CHICKEN  LICE. 

The  red  chicken  louse  (Dermanyssus  gallina^)  has  as  its  host 
chickens  and  other  feathered  animals.  It  will,  however, 
attack  horses  and  cattle,  j)r()ducing  eczema.  In  cattle  it  has 
been  known  to  enter  the  ears,  causing  an  external  otitis.  In 
rare  instances  lice  penetrate  the  middle  ear,  causing  symp- 
toms of  cerebral  excitement. 

SKIN  FILARIA. 

Thread-worms,  which  are  parasitic,  invade  the  skin  and 
subcutaneous  tissue  of  animals.  The  following  \  aricties  are 
the  most  common: 


SKIX  FI LABIA  271 

Filaria  Irritans. — This  is  a  silver-white  larva  2  or  3  mm. 
long,  the  adult  form  of  which  is  miknown.  It  lives  in  the 
subcutaneous  connective  tissue  of  the  horse  and  is  the  cause 
of  a  skin  disease  commonly  known  as  "summer  sores,"  or 
granular  dermatitis.  The  lesion  manifests  itself  first  by  little 
nodules  which  appear  in  the  harness  rests,  legs,  or  other  parts 
of  the  body.  The  nodules  ultimately  erupt,  leaving  behind 
ulcers  which  are  covered  with  reddish-brown  granulations. 
On  careful  examination  small  hempseed-sized,  yellow,  cheesy 
or  calcified  foci  may  be  noted.  In  these  centres  the  filarial 
larvae  are  found.  The  ulcers  show  a  tendency  to  spread  and 
are  very  obstinate  to  treat.  This  is  due  to  biting  and  rubbing 
by  the  patient  and  the  irritation  caused  by  flies.  The  ulcers 
usually  heal  after  the  fly  season,  but  recur  the  foUo^xing 
summer. 

Treatment. — Treatment  consists  in  preventing  the  animal 
from  rubbing  or  biting  the  part  and  pre^•enting  flies  from 
reaching  it.  It  is  recommended  to  paint  the  ulcer  with  a 
thin  layer  of  sulphide  of  arsenic,  which  forms  a  dry  scab, 
under  which  healing  occurs.  Picric  acid  (1  per  cent.)  and 
glycerin  are  also  good.  Other  remedies  are  chloroform,  ether, 
or  iodoform  applied  daily.  Sometimes  the  hot  iron  is  eftec- 
tive,  as  is  curetting  or  even  the  total  extirpation  of  the  aftected 
area. 

Filaria  Hemorrhagica. — This  is  a  fine  thread-like  worm 
28-70  mm.  long  which  is  parasitic  and  lives  in  the  sub- 
cutaneous and  intermuscular  connective  tissue  of  Oriental 
horses.  It  causes  during  the  siunmer  months  skin  hemor- 
rhages. The  blood  raises  the  epidermis  or  skin  in  the  form 
of  a  hazel-nut-sized  or  small  hematoma  which  ruptures  in 
one  or  two  hours,  its  contents  flowing  over  the  skin.  Usually 
a  nimiber  of  these  nodules  occur  close  together  so  that  the 
invaded  area  is  covered  with  blood.  The  condition  disappears 
in  winter  to  recur  the  following  summer.  Healing  usually 
occiu's  spontaneously.  The  disorder  is  not  serious,  although 
object  ional)le. 

Treatment. — The  treatment  consists  in  washing  the  skin 
with  an  antiseptic  and  protecting  the  bloody  area  from  the 
harness. 


272  DISEASES  OF   THE  SKIN 

LIP-AND-LEG  ULCERATION  OF  SHEEP. 

Necrobacillosis.  ^ 

Definition. — Necrobacillosis  is  an  iiiflaimnatory  process 
which  terminates  in  necrosis  of  the  skin  and  mucous  mem- 
branes attacking  the  mouth,  lips,  legs,  feet  and  external 
genital  organs  of  sheep. 

Occurrence. — The  disease  is  closely  allied  to  necrotic  sto- 
matitis of  calves  and  pigs.  It  attacks  sheep  on  the  Western 
ranges,  particularly  in  Montana  and  Wyoming,  where  it 
sometimes  assinnes  a  malignant  form,  causing  considerable 
losses  through  deaths,  lost  service  of  bucks,  and  abortion  in 
ewes.  ^Vhile  during  favorable  Aveather  and  with  abundant 
feed  the  disorder  is  mild,  where  opposite  conditions  prevail 
it  is  often  malignant,  leading  to  the  loss  of  from  10  to  20 
per  cent,  of  the  sheep  herd.  The  disease  has  been  introduced 
into  the  Eastern  States  by  the  importiition  of  Western  sheep. 
It  also  exists  in  England,  on  the  continent  of  Europe,  and  has 
been  reported  from  New  Zealand. 

Etiology. — The  cause  of  the  disease  is  the  Bacillus  necro- 
})h()rus,  which  enters  skin  lesions  often  made  by  cactus  or 
other  sharp-pointed  ])articles  of  plants.  The  disease  is  most 
frequent  during  cold  seasons  and  among  sheep, which  are 
pasturing  among  thistles,  cacti  and  briers.  It  is  transmissible 
l)oth  by  natural  and  artificial  inoculation. 

Symptoms. — From  a  clinical  standpoint  four  forms  are 
described:  (a)  the  lip-and-leg,  (6)  the  venereal,  (c)  the  foot- 
rot,  (d)  the  sore  mouth  of  lambs. 

(a)  Lip-aiid-lrg  Form.  The  first  stages  are  those  of  acute 
inflammation  of  the  skin,  usually  of  the  lips.  Pustules  develop 
which  undergo  puriform  softening,  erupt  and  lead  to  ulcers. 
The  ulcers  are  usually  covered  with  exudate  which  dries  to 
form  dark  gray-colored  crusts.  By  confluence  a  large,  irregu- 
lar shaped  scab  forms  along  the  lip  margins  and  extending 
upwardly  in  front  to  the  nasal  openings.  The  lips  are  swollen 
and  present  a  scabby  or  warty  appearance.  The  appetite 
usually  remains  good,  though  the  prehension  of  food  is  difficult 
owing  to  the  sensitiveness  of  the  lips.     In  some  cases  the 


LIP-AXD-LEG   ULCERAriOX  OF  SHEEP  273 

cheeks  may  also  be  involved  or  even  the  eyelids.  Occasion- 
ally the  mucous  membrane  of  the  nose  and  mouth  is  invaded. 

Quite  commonly  lesions  occur  on  the  legs.  The  favorite 
seat  is  about  the  coronet,  under  the  fetlock  or  in  the  neighbor- 
hood of  the  fetlock-joint.  The  ulcers  upon  the  legs  are  similar 
to  those  found  upon  the  lips;  they  are  covered  by  a  thick,  dry 
crust  which  when  remo\ed  exposes  a  granulating  surface 
covered  with  pus. 

(6)  Venereal  Form.  In  this  form  the  external  genital 
organs  of  both  males  and  females  are  involved.  It  may  be 
associated  with  the  lip-and-leg  form,  but  not  infrequently 
occurs  independently.  In  males  the  skin  of  the  sheath,  espe- 
cially at  its  orifice,  is  inflamed.  The  first  symptom  is  the  ap- 
pearance of  one  or  more  light  yellow-colored  centres,  necrotic 
areas,  which  appear  at  the  junction  of  the  skin  and  mucous 
membrane  of  the  prepuce.  Soon  there  develops  an  ulcer 
which  usually  extends  outwardly  over  the  skin  rather  than 
inwardly  over  the  mucous  membrane.  By  coalescence  the 
whole  swollen  sheath  may  be  covered  with  ulcers.  Occasion- 
ally the  pendant  portion  of  the  prepuce  may  slough.  In 
wethers  the  penis  is  rarely,  if  ever,  attacked.  In  bucks,  how- 
ever, the  necrosis  attacks  the  penis,  which  swells  ("big 
pizzle"),  becomes  ulcerous  on  its  surface,  and  occasionally 
gangrenous,  the  tlistal  portion  of  the  organ  not  umarely 
sloughing  off. 

In  ewes  the  ulcerations  occur  in  the  skin  and  mucous 
membrane  of  the  vulva,  the  ventral  surface  of  the  tail,  and 
the  perineal  region.  Occasionally  the  \-agina  may  be  involved, 
leading  to  a  discharge. 

(c)  Foot-rot  Form. — The  foot-rot  form  involves  at  first  the 
interdigital  spaces,  the  erosions  usually  making  their  first 
appearance  at  the  heel.  The  inflammation  invades  the  hoof 
matrix,  leading  to  the  discharge  of  a  thin  ichor  which  has  a 
very  characteristic  pungent,  penetrating  odor.  The  foot-rot 
form  may  attack  any  sheep  in  the  herd  irrespective  of  age  or 
sex. 

(d)  Sore-mouth  Form. — This  form  is  seen  in  lambs  during 
the  fall  of  the  year.  The  symptoms  are  similar  to  those  of 
the  lip  form  in  older  sheep.     The  lips  of  the  lambs  swell, 

18 


274  DISEASES  OF  THE  SKIN 

prehension  of  food  becomes  diflficult,  and  the  patient  falls  off 
in  flesh  and  remains  stunted  in  gro\vth.  At  the  junction  of 
the  mucous  membrane  and  skin  of  the  hps,  nodules  or  ne- 
crotic areas  appear.  By  confluence  lar«];e,  diffuse,  fissured 
scabs  form,  covering  in  some  cases  the  whole  muzzle.  If 
the  scabs  are  removed  raw,  bleeding  surfaces  or  pus-covered , 
ulcerous  areas  are  exposed.  In  some  cases  the  inflammation 
spreads  to  the  mucous  membrane  of  the  mouth,  forming 
ulcers  or  soft  red,  fungoid  proliferations.  The  expirium  is 
very  offensive,  resembling  that  of  Limburg  cheese. 

Treatment. — Once  the  disease  has  broken  out  in  a  herd  or 
band  of  sheep,  treatment  should  be  begun  early  and  apjilied 
energetically.  In  milder  cases  of  the  lip-and-lcg  form  the 
scabs  and  shreds  of  tissue  from  the  diseased  areas  should  be 
scraped  off  and  antiseptics  applied  to  the  raw  surface  three 
or  four  times  weekly.  A  mixture  of  creolin  (5  parts),  sub- 
limed sulphur  (10  parts),  mutton  tallow,  vaselin,  or  lard 
(100  parts)  mixed  to  form  an  ointment  has  been  found  very 
serviceable.  In  aggravated  cases  the  scab  should  be  removed 
and  all  diseased  tissue  from  the  ulcer  scraped  away.  The  raw 
surface  may  then  be  touched  with  zinc  chlorid  (10  per  cent.) 
or  nitric  acid  (15  per  cent.).  These  caustics  should  be  applied 
very  carefully.  The  unskilful  and  indiscriminate  use  of  them 
will  do  more  harm  than  good.  As  it  will  require  a  month  or 
more  to  produce  a  cure  in  severe  and  chronic  cases  the  expense 
of  the  treatment  may  exceed  the  value  of  the  sheep.  Such 
cases  had  best  be  dispatched. 

Where  a  large  number  of  range  sheep  are  affected  with  the 
leg  or  foot-rot  form,  hand  treatment  is  not  always  feasible. 
In  these  cases  the  shecj)  may  be  waded  through  a  trough  con- 
taining creolin  or  sheep-dip  solution  (')  per  cent.)  three  times 
a  week.  Bad  and  obstinate  cases  which  do  not  yield  to  these 
foot  baths  may  be  hand-treated.  In  the  foot-rot  form  it  is 
often  necessary  to  use  the  knife  skilfull\'  to  remove  all  dis- 
eased or  loosened  horn. 

The  venereal  form  of  the  disease  recjuires  careful  treatment. 
In  bucks  the  diseased  penis  should  be  forced  out  of  the  sheath 
and  the  necrotic  areas  on  its  surface  carefully  cauterized  with 
zinc  chlorid  or  nitric  acid.     This  mav  be  followed  bv  dailv 


BIGHEAD  OF  SHEEP  275 

injections  of  permanganate  of  potash  (1  to  500)  or  a  sheep- 
dip  sohition  (1  per  cent.)-  In  females  the  same  treatment 
may  be  appHed  to  the  vulva  or  vagina.  Abscesses  containing 
inspissated  pus  should  be  opened,  their  contents  evacuated 
and  antiseptics  applied.  Ulcers  of  the  mucosa  of  the  mouth  of 
lambs  may  be  treated  with  creolin  (1  per  cent.)  or  boric  acid 
solution  (3  per  cent.).  Advanced,  aggravated  cases  which 
obstinately  resist  treatment  should  be  killed. 

After-treatment  consists  in  giving  the  sheep  access  to 
medicated  salt  (crude  carbolic  acid  S  iv>  poured  over  ordinary 
barrel  salt,  12  quarts,  and  thoroughly  mixed).  It  is  also 
recommended  to  dip  all  recovered  animals  before  turning 
them  out  on  uninfected  pastures  or  premises.  A  complete 
disinfection  of  all  pens,  corrals,  walls,  partitions,  racks,  and 
troughs  should  be  made.  The  manm-e  and  surface  soil  of  the 
corral  should  be  removed  and  the  ground  sprinkled  with 
disinfectants. 

Prophylaxis. — Healthy  sheep  should  not  be  permitted  to 
pasture  on  infected  ranges  until  a  winter  has  passed,  after 
which  the  pasture  is  safe.  Obviously  with  range  sheep  this 
precaution  cannot  always  be  employed.  No  new  sheep  should 
be  introduced  into  the  herd  without  being  subjected  first  to  a 
two  weeks'  quarantine.  If  no  cases  of  lip-and-leg  ulceration 
develop  in  this  time  it  will  be  safe  to  place  them  with  the 
original  flock.  The  sheep  herd  should  be  carefully  supervised 
and  frequently  inspected  to  find  any  chance  cases  of  this 
disease.  All  sick  sheep  should  be  immediately  removed  and 
if  possible  given  proper  hand  treatment. 

BIGHEAD  OF  SHEEP. 

Definition. — Bighead  is  a  peculiar  condition  afi'ecting  West- 
ern sheep  and  is  characterized  b}'  the  appearance  of  swellings 
about  the  head  and  ears. 

Occurrence. — Bighead  is  not  an  uncommon  disease  in  the 
Western  States  where  sheep-raising  is  an  important  industry. 
Cases  are  reported  from  Idaho,  Nevada,  Utah,  and  Wyo- 
ming. It  resembles  the  so-called  buckwheat  poisoning  (fago- 
pyrism)    of    Europe.    The    disease    is    not    communicable. 


270  DISEASES  OF  THE  SKIN 

Neitlier  sheep  nor  other  animals  can  be  infected  by  natnral 
or  artificial  means.  While  some  outbreaks  are  comparatively 
mild,  not  infrequently  the  affection  assumes  a  malignant 
form  which  leads  to  considerable  losses,  causing  it  to  liecome 
a  matter  of  importance  to  sheepmen. 

Etiology. — The  cause  of  bighead  has  not  yet  been  deter- 
mined. Outbreaks  occur  usually  during  the  spring  and  early 
summer  while  the  sheep  are  being  driven  from  the  winter  to 
the  summer  ranges  and  before  they  are  sheared.  Climatic 
conditions  evidently  predispose  to  the  disorder,  which  is  most 
apt  to  appear  following  a  cold,  stormy  night,  especially  if  the 
sheep  are  driven  the  next  day  in  the  hot  sunshine.  The  dis- 
ease is  most  apt  to  affect  adult  sheep;  it  is  rarely  seen  in 
young  lambs.  The  condition  of  the  sheep  seems  to  hare  little 
to  do  with  the  occurrence  of  an  outbreak;  it  is  as  apt  to 
attack  the  well  nourished  as  it  is  individuals  poor  in  flesh. 
Buckwheat  feeding  has  failed  to  produce  in  experimental 
animals  symptoms  of  the  disorder. 

Symptoms. — The  symptoms  which  precede  the  appearance 
of  the  swellings  are  jerking  movements  of  the  head;  the  sheep 
shakes  its  head  and  rubs  it  against  objects.  The  eyesight 
seems  to  be  impaired,  the  sheep  often  running  into  other 
sheep  and  objects  found  in  its  path.  Symptoms  of  cerebral 
excitement  are  not  uncommon,  in  some  instances  the  sheep 
show  maniacal  phenomena.  Obviously  sheep  so  affected  often 
leave  the  flock,  become  lost,  and  die  of  exhaustion  and  ex- 
posure, or  become  the  ])rey  of  coyotes. 

Later  it  will  be  noted  that  the  ears  begin  to  turn  red  and 
become  swollen.  P'inally  the  swellings  extend  over  the  cheeks 
and  face,  closing  the  eyes,  or  in  some  cases,  if  the  retrobulbar 
tissue  becomes  in\'olved,  may  force  the  eyeballs  from  their 
sockets.  The  swellings  may  become  very  tense  and  (Iroi)s  of 
serum  ooze  from  them.  In  some  cases  the  lips,  cheeks,  and 
tongue  are  so  swollen  that  it  is  impossible  for  the  animal  to 
eat  or  drink.  DysjMica  is  a  common  symptom.  The  tem- 
perature ranges  from  104°  to  107°  F.  The  skin  often  sloughs 
over  the  swollen  areas,  and  the  wool  o\'er  the  entire  body  may 
be  shed.  Pregnant  ewes  fre(iucntl\'  abort.  Sheep  which 
recover  are  usually  left  permanently  unthrifty. 


BIGHEAD  OF  SHEEP  277 

Treatment. — Internal  treatment  (belladonna,  turpentine, 
strychnin,  arsenic,  (li<,ntalis)  has  been  found  useless.  On  the 
other  hand,  smearinj;-  the  head  of  the  affected  sheep  with 
vaselin  or  olive  oil,  especially  if  the  sheep  are  permitted  to 
rest  in  the  shade,  has  been  of  service.  Scarifying  the  swellings 
does  no  good,  and  exposes  the  parts  to  further  infection. 

Prophylaxis. — The  disorder  is  prevented  by  not  driving  the 
sheep  too  far  or  too  rapidly  during  the  heat  of  the  day,  espe- 
cially before  shearing  in  the  spring.  Affected  sheep  should  be 
dropped  out  of  the  herd  and  the  entire  band  allowed  rest  in 
the  shade  if  possible.  vSheepmen,  believing  the  trouble  due  to 
poisonous  plants,  often,  when  a  case  of  bighead  develops  in  a 
band,  rush  the  sheep  to  get  them  away  as  rapidly  as  possible 
from  the  region  in  which  the  supposed  poisonous  plants  exist. 
This  in  itself  tends  to  produce  the  trouble  they  seek  to  avoid. 


PART   XI. 
INFECTIOUS  DISEASES. 


CHAPTER  I. 
ACUTE  GENERAL  INFECTIOUS  DISEASES. 

ANTHRAX. 

Definition. — Anthrax  is  an  acute,  febrile  infectious  disease 
caused  by  the  Bacterium  anthracis  affecting  all  domesticated 
animals  with  the  probable  exception  of  fowls.  It  is  character- 
ized postmortem  by  splenic  enlargement  and  serohemorrhagic 
infiltration  of  the  subserous  and  subcutaneous  connective 
tissues. 

Occurrence. — Anthrax  is  a  disease  largely  confined  to  per- 
manently infected  districts.  Generally  speaking  it  is  rare  in 
the  United  States,  occurring  only  sporadically  in  the  North, 
although  in  some  parts  of  the  South,  especially  along  the  rich 
lowlands  of  the  lower  INIississippi,  it  appears  enzootically, 
attacking  numbers  of  horses  and  mules.  The  disease  is  more 
common  in  herbivora  than  in  either  omnivora  or  carnivora. 
Ends  are  probably  never  infected  naturally,  although  the 
disease  may  be  with  difficulty  artificially  transmitted.  The 
pigeon,  however,  forms  an  exception,  being  very  susceptible 
to  infection  with  antln-ax  cultiu-es. 

Etiology. — The  Bacterium  antln-acis,  which  occurs  in  the 
tissues  in  the  form  of  rods  and  in  the  gastro-intestinal  tract 
and  outside  the  body  in  the  form  of  spores.  The  spore 
possesses  a  remarkable  vitality  and  may  remain  virulent  for 
months  in  soil,  maniu-e,  foodstuffs,  water,  and  in  the  blood, 
hide,  wool,  or  hair  of  animals  which  have  died  of  the  disease. 


280         ACUTE  GENERAL  INFECTIOUS  DISEASES 

Natural  Infection. — («)  Dnjcstivc  Tract. — In  animals  the 
usual  mode  of  infection  is  through  the  digestixe  tract,  the 
si)()res  being  taken  in  with  the  food  and  water  of  infected 
districts.  This  applies  i)articularly  to  grazing  sheep  and 
cattle,  especially  if  feeding  on  low,  wet  pastures  subject  to 
overflow.  Certain  fields,  notably  those  in  which  the  carcasses 
of  anthrax  animals  ha\e  lain  or  were  buried  (shallow  graves), 
or  contaminated  with  the  (Iropi)ings  or  blood  of  jxitients 
suffering  from  the  disease,  are  especially  dangerous  in  this 
regard.  It  is  probable  that  healthy  animals  may  carry  spores 
in  the  digesti\'e  contents  without  becoming  infected  them- 
selves, their  droi)pings,  however,  j)olluting  the  soil,  drinking 
water,  and  forage,  thus  infecting  other  less  resistant  animals. 
The  blood  of  the  living  or  dead  anthrax  animal  is  also  in- 
fective. Soil  and  water  can  be  contaminated  by  the  oflFal  of 
tanneries,  hair-  or  rag-sorting  establishments.  Flesh-eating 
animals  can  infect  themselves  by  eating  meat  or  blood  con- 
taining anthrax  spores.  In  this  way  dogs  and  swine  take  the 
disease.  As  fresh  meat  and  blood  usually  contain  only  bacilli 
which  are  destroyed  by  the  digestive  juices,  it  is  not  as 
dangerous  as  when  stale.  However,  if  very  large  quantities 
are  eaten,  infection  may  follow,  some  of  the  bacilli  escaping 
the  destructive  influences  of  the  gastric  fluids.  In  swine  the 
crypts  of  the  tonsils  may  serve  as  ])oints  of  attack  for  the 
spores  ta-jcen  in  with  the  food  and  water.  Milk  does  not  usually 
contain  either  spores  or  bacilli,  but  at  times,  especially  when 
the  milk  is  bloody,  they  may  be  i)resent. 

(6)  Respiratory  Tract. — The  inhalation  of  dried  spores  from 
contaminated  dust,  wool,  hair,  or  rags  is  a  common  mode 
of  infection  in  man.  \Yhile  this  is  also  probable  in  animals, 
no  proof  is  available. 

(c)  Skin. — An  infection  through  the  intact  skin  is  not  prob- 
able. When  the  skin  is  wounded,  however,  it  may  follow. 
The  prevailing  enzo()tics  of  anthrax  among  liorses  and  mules  in 
the  lower  Mississippi  valley  are  said  to  be  induced  through 
skin  infection,  the  gad  fly  (Tabanidte),  horse  flies,  and  even 
mosquitoes  being  accused  as  carriers  of  the  infection.  Some 
authorities,  however,  deny  insect  transmission  in  anthrax. 


ANTHRAX  281 

Necropsy.^ — As  man  is  ([iiite  susceptible  to  anthrax,  every 
precaution  should  be  taken  in  hoklinjj;  necropsies  to  'j;uard 
against  infection.  The  blood,  flesh  and  digestive  contents 
should  not  be  permitted  to  pollute  the  forage  or  soil,  and 
carrion  birds,  dogs,  etc.,  kept  aloof  until  the  carcass  and  offal 
are  made  innocuous. 

The  cadaver  is  usually  greatly  bloated,  rapidly  decompos- 
ing and  rigor  mortis  little  developed.  The  mucous  mem- 
branes are  cyanotic,  the  rectum  protruding  and  dark  blood 
flows  from  the  natural  openings.  If  swellings  in  the  skin  and 
subcutis  are  present  they  appear  on  cut  surface  hemorrhagic- 
gelatinous  or,  if  older,  lardaceous,  the  overlying  skin  dis- 
colored and  in  part  necrotic.  Throughout  the  body  the 
organs  show  petechi^e,  ecchymoses  and  blood  extravasations. 
Collections  of  blood-stained  fluid  are  noted  in  the  abdominal 
and  thoracic  cavities,  and  in  the  pericardium.  The  spleen  is 
three  to  six  times  its  normal  size,  the  parenchyma  black 
and  soft,  even  fluid.  Spontaneous  rupture  of  the  capsule 
sometimes  occurs.  The  blood  is  dark,  varnish-like,  staining 
the  fingers  and  little  coagulated.  The  lining  of  the  aorta  is 
diffusely  reddened.  The  intestinal  mucosa,  especially  in  the 
small  bowel,  is  edematously  swollen,  jelly-like  and  sometimes 
several  centimeters  thick.  Necrosis  of  the  superficial  layers 
is  sometimes  noted.  Peyer's  plaques  and  the  solitary  follicles 
are  swollen,  projecting  into  the  lumen  of  the  intestine  Ha  dark 
red  elevations.  The  lungs  are  edematous,  congested.  The 
mucous  membrane  of  the  larynx  is  swollen,  congested,  and 
ecchyniosed.    The  lymph  glands  are  swollen  and  blood-shot. 

In  the  spleen  pulp  and  blood,  hinph  glands  and  parenchy- 
matous organs  anthrax  bacilli  are  found. 

In  swine  the  necropsy  lesions  are  confined  mostly  to  the 
throat.    The  spleen  is  quite  often  normal  in  this  animal. 

Symptoms. — In  general,  anthrax  is  characterized  clinically 
by  its  sudden  appearance,  stormy  course  leading  to  death  in 
one  or  two  days,  high  fever,   severe  general  disturbance, 

1  The  postmortem  lesions  vary  greatly  in  anthrax.  In  peracute  cases 
the  changes  are  very  little  marked,  and  the  bacilli  not  numerous.  The 
description  given  above  applies  to  the  usual  acute  or  subacute  case  and 
may  be  considered  typical. 


282         ACUTE  GENERAL  INFECTIOUS  DISEASES 

tendency  for  petechia'  to  appear  On  mucous  nienihranes, 
bleeding  from  natural  openings,  skin  edemas,  colic,  dyspnea, 
cerebral  excitement,  and  the  ])resence  of  the  bacterium 
anthracis  in  the  blood. 

Period  of  Tncuhat  ion . — 'i'he  period  of  incubation  is  from  one  to 
fourteen  days.  The  symptoms  vary  greatly,  depending  upon 
the  severity  of  the  attack  and  the  resistance  of  the  patient, 
which  factors  largely  determine  the  course  of  the  disease. 
They  also  vary  with  the  ])oint  of  attack,  depending  on  whether 
the  lungs,  bowel,  or  skin  are  primarily  involved.  It  is  cus- 
tomary clinically  to  classify  anthrax  as : 

(a)  Peracitte  Anthrax  {"Apoplectic  or  Explosive  Anthrax," 
Anthrax  Acntessivnis) .■ — As  a  rule  this  form  appears  in  the 
beginning  of  the  outbreak.  The  animals  are  usually  found 
dead,  or  die  in  a  few  minutes  after  sjTiiptoms  of  asphyxia,  the 
patient  dropping  to  the  ground  in  convulsions,  foam  coming 
from  the  nostrils  and  blood  from  the  natural  openings. 

{h)  Acute  and  Snhacnfe  Anthrax  {Anthrax  ^icutnfi  et  Snb- 
acutiis). — This  form  lasts  usually  ten  hours  to  se\'eral  days. 
The  patient  shows  high  fever  from  105°  to  107°  F.  The  pulse 
is  rapid,  weak,  and  irregular,  the  heart  beat  tumultuous. 
The  respirations  are  (l>'spncic  and  sometimes  stertorous.  The 
visible  mucous  membranes  are  cyanotic  and  dotted  with 
petechia\  The  patient  may  at  first  show  symptoms  of  cere- 
bral excitement,  which  are  soon  followed  by  stupor  and 
vertigo.  Quite  often  the  ])atient  is  down,  unable  to  rise.  In 
some  cases  (especially  in  horses)  marked  colic  symptoms 
occur,  but  bloating  is  rarely  noted.  In  the  ox  it  may  occur. 
In  the  earlier  stages  there  is  constipation,  the  animal  straining 
as  if  to  defecate,  the  rectum  protruding;  bloody  diarrhea 
usually  follows.  The  urine  in  the  latter  stages  may  be  dark 
red  and  contain  blood.  In  niilk-gi\ing  animals  the  milk  flow 
stops  during  the  high  fever;  in  rare  instances  the  milk  is 
bloody  and  bitter  to  the  taste.  In  pregnant  animals  abortus 
occurs.  Death  usually  ensues  under  asphyxia.  While  re- 
covery is  rare,  toward  the  end  of  an  outbreak  a  few  cases 
may  get  well,  the  s}^nptoms  rapidly  subsiding. 

(c)  Cidanecrus  Anthrax  {Malignant  Carbuncle  or  Pnstnle). 
■ — ^This  form  is  commonest  in   horses  and  mules.     Acute, 


ANTHRAX  283 

edematous  swellings  appear  on  different  parts  of  the  body. 
The  favorite  seats  are  under  the  throat,  on  the  chest,  flanks, 
and  loins.  The  swellings  are  at  first  hot  and  painful,  but  later 
become  colder  and  less  sensitive.  They  are  usually  flat  and 
subcutaneous,  and  in  the  early  stages  the  overlying  skin  and 
hair  may  appear  normal.  Thus  they  may  be  overlooked. 
When  swellings  occur  in  the  throat,  symptoms  of  edema  of 
the  glottis  follow.  In  swine  the  disease  usually  involves  the 
throat  with  swelling  of  the  parotid  and  laryngeal  regions, 
later  extending  to  the  face.  The  patient  shows  dyspnea  and 
dysphagia.  The  mucous  membranes  are  cyanotic  and  show 
petechise;  the  same  symptoms  may  also  occur  in  the  skin. 
Death  results  from  asphyxia. 

Course. — The  course  in  peracute  cases,  as  noted,  is  very 
rapid,  lasting  only  fifteen  minutes  to  one  hour.  In  acute  cases 
it  may  last  one  to  tlii*ee  days,  and  in  subacute  ones  a  week  or 
more,  exceptionally  ending  in  recovery.  In  the  horse  the 
cutaneous  and  bowel  (colic)  forms  seem  to  predominate;  in 
the  ox  anthrax  occurs  as  a  general  febrile  disease  with  a  ten- 
dency to  bowel  hemorrhages,  skin  swellings  being  rare.  In 
the  sheep  the  course  is  usually  stormy,  the  disease  rarely 
locating  in  special  organs,  and  assumes  the  form  of  a  pure 
septicemia. 

Diagnosis. — Intra  vitam  a  diagnosis  of  anthrax  can  rarely  be 
made  with  any  degree  of  certainty.  As  a  rule  a  necropsy 
must  first  be  held  and  a  bacteriological  examination  made  of 
the  blood  and  parenchymatous  tissues  (spleen  pulp).  Clin- 
ically, anthrax  resembles  certain  forms  of  forage  poisoning, 
hemorrhagic  septicemia,  black-leg,  malignant  edema,  and 
Texas  fever.  Peracute  cases  might  easily  be  confused  with 
edema  of  the  glottis,  cerebral  congestion  (sunstroke),  and 
acute  pulmonary  edema.  iVcute  poisonings  might  also  be 
taken  for  it  (temperature  high  here  only  in  the  latter  stages). 
It  is  sometimes  sufficient  to  draw  blood  from  the  suspected 
patient  (ear  or  foot)  and  inoculate  with  it  a  guinea-pig  or 
white  mouse,  which,  if  the  blood  contains  anthi'ax  bacilli,  will 
succumb  in  twenty-four  to  thirty-six  hours.  The  blood  and 
spleen  pulp  will  contain  the  capsulated  rods,  which  may  be 
determined  by  proper  staining. 


284         ACUTE  GENERAL  INFECTIOUS  DISEASES 

Prognosis. — The  i)rognosis  in  anthrax  is  bach  Tlie  jiiortahty 
is  70  to  90  i)er  cent.  In  subacute  cases  recovery  takes  place 
occasionally,  and  usually  quite  unexpectedly,  beginning  on 
the  second  or  third  day.  Nearly  all  i)eracute  and  acute  cases 
die.  In  cutaneous  anthrax  an  early  surgical  treatment  of  the 
carbuncle  is  occasionally  life-saving. 

Treatment. — A  medicinal  treatment  is  rarely  of  value.  In- 
ternally coal-tar  products  (creolin,  lysol  (5  j)  five  times  daily) 
are  recommended.  Turpentine,  chlorin  water,  hydrochloric 
acid,  and  calomel  ha^'e  been  tried  witli  small  success.  Sur- 
gically the  carbuncles  may  be  slit  open  and  injected  with  anti- 
septics (bichlorid  of  mercury  1  to  2000  in  alcohol  for  horses; 
iodin  tincture  in  cattle).  In  infected  districts  the  use  of  the 
Pasteur  protective  vaccination  is  recommended.  As  the 
vaccination  material  contains  living  though  attenuated  germs 
caution  must  be  exercised  in  its  application.  It  is  possible  to 
spread  anthrax  by  its  use  if  carelessly  handled.  Protective 
and  curative  inoculation  with  immune  serum  is  employed  in 
Europe  and  South  America.  A  passive  immunity  lasting 
two  or  three  weeks  is  obtainal)le  by  its  use.  When  infection 
continues  to  threaten  an  acti\'e  immunity  is  produced  by  later 
\-accinating  with  attenuated  anthrax  cultures.  As  in  hog 
cholera  a  combined  actWe  and  passive  immunity  may  be 
acquired  by  the  simultaneous  injection  of  immunizing  serum 
and  attenuated  anthrax  culture.  The  "serum  alone"  treat- 
ment is  employed  when  the  animal  is  already  diseased;  the 
"simultaneous"  injections  usually  before  the  disease  becomes 
manifest.  Uei)orts  concerning  the  Nalue  of  anti-anthrax  sera 
are  conflicting.  Occasional  fatal  anaphylactic  phenomena 
have  followed  the  inoculation. 

Prevention. — All  anthrax  cadavers  should  be  either  com- 
pletely cremated  or  buried  at  least  six  feet  deep.  Indiscrimi- 
nate transportation  and  opening  of  the  carcasses  should  be 
avoided.  If  feasible  they  should  be  buried  where  they  die. 
Infected  fields  should  be  tile-drained  and  cropped.  Stagnant 
pools  should  be  eliminated,  as  they  not  only  harbor  spores 
but  form  the  breeding  places  of  insects  which  may  be  carriers 
of  infection.  Hair,  wool,  hides,  harness,  stable  utensils,  etc., 
should  be  disinfected  by  using  heat  or  a  2  per  cent,  formal- 
dehvd  solution. 


MALIGAAA'T  EDEMA  285 

Infected  premises,  barns,  sheds,  stables,  etc.,  should  be 
thoroughly  disinfected  by  using  chlorid  of  lime,  or  an  abun- 
dance of  quicklime  in  the  form  of  whitewash  or  dry.  The 
carcass  should  not  be  skinned,  the  flesh  should  not  be  fed  to 
dogs  or  swine,  and  the  use  of  the  milk  forbidden. 


MALIGNANT  EDEMA. 

Definition. — ^Malignant  edema  is  an  acute,  fatal,  infectious 
disease,  characterized  by  the  formation  of  edematous  swellings, 
which  later  become  emphysematous  and  occur  in  the  region  of 
a  wound  infected  with  the  specific  anaerobic  Bacillus  oedematis 
maligni. 

Occurrence. — The  disease  is  widely  distributed.  It  affects 
mostly  horses,  following  accidental  or  surgical  wounds.  In 
cattle  it  occurs  from  obstetrical  operations,  and  in  sheep  may 
result  from  cuts  received  during  shearing.  In  the  United 
States  it  is  one  of  the  commonest  wound-infection  diseases 
extant. 

Etiology. — The  Bacillus  oedematis  maligni,  which  is  found  in 
both  the  rod  and  spore  stages  in  soil,  manure  (droppings), 
dust,  decomposing  vegetable  matter  and  pointed  water. 

Natural  Infection. — Horses  and  sheep  seem  most  susceptible 
to  the  infection,  while  cattle  and  swine  offer  more  resistance. 
The  infection  is  always  through  a  wound  (surgical  or  acci- 
dental) in  the  skin  or  mucous  membrane.  In  practice  malig- 
nant edema  most  frequently  follows  surgical  operations  (poll 
evil,  castration,  plilebotomy),  the  use  of  the  unsterilized 
hypodermic  syringe,  rough  obstetrical  manipulations,  skin 
cuts  from  careless  shearing  of  sheep,  etc.  It  may  also  follow 
accidental  wounds  due  to  wood  splinters,  nails,  or  other  pene- 
trating objects  which  carry  the  infection.  Feeding  and  in- 
halation experiments  with  the  bacilli  and  spores  of  malignant 
edema  gave  negative  results.  The  intact  skin  and  mucous 
membrane  are  not  infectable.  Infection  through  a  necrotic 
area  (ulcer)  is  probable.  Normally  granulating  wounds  are, 
however,  very  resistant  to  infection.  Inoculations  with  pure 
cultures  are  not  successful  unless  phagocytosis  is  overcome  by 


286         ACUTE  GENERAL  INFECTIOUS  DISEASES 

luechaiiical  (sand  i)artick\s)  or  chemical  agencies  (lactic  acid) 
or  the  toxins  of  other  bacteria  which  may  be  present  (staphy- 
lococci). 

Symptoms. — \n  the  neighborhood  of  the  infected  wonnd  a 
rather  diffuse  edematous  swelling  a])])ears.  The  swelling  is 
at  first  painful,  firm,  and  hot,  but  later  becomes  softer,  less 
painful,  and  on  palpation  crepitates.  It  spreads  rapidly  and 
in  a  few  hours  can  involve  the  whole  body  and  head.  In  a 
horse  so  afflicted  the  patient  assumes  the  appearance  of  a 
hippopotamus.  With  the  advance  of  the  external  swelling 
dyspnea  develops  with  foamy  nasal  discharge  (lung  edema), 
cyanotic  mucous  membranes,  and  ra])id,  weak,  irregular 
pulse.  The  temperature  is  elevated  early  and  does  not  sink 
to  normal  until  the  patient  becomes  moribimd. 

In  cows  infected  during  obstetrical  manipulations,  in  two 
to  four  days  the  lips  of  the  vulva  begin  to  swell,  the  swelling 
rapidly  involving  the  perineum,  thighs,  an<l  udder.  There  is 
an  offensive  brownish  discharge  from  the  vagina.  The  tem- 
perature is  up  and  bloating  and  diarrhea  noted. 

Diagnosis. — The  cardinal  symptoms  of  malignant  edema 
are:  rapid  development,  emphysematous  character  of  the 
swellings,  high  fever,  and  fatal  course.  It  resembles  black- 
leg in  cattle,  but  may  be  distinguished  from  this  disease  by 
the  following:  malignant  edema  usually  affects  the  repro- 
ductive organs  of  cows  at  the  time  of  ])arturition;  it  aft'ects 
connective  tissue  rather  than  muscle,  is  not  confined  to  young 
cattle,  and  appears  in  districts  free  from  black-leg.  Black-leg 
is  common  in  the  United  States,  and  occurs  enzootically, 
while  malignant  edema  is  rare  in  cattle  and  is  sporadic.  It 
would  hardly  be  confused  with  i)hlegm()ns  resulting  from  pus 
infection.  Such  swellings  do  not  develop  so  rapidly,  do  not 
crepitate,  and  are  not  usually  fatal.  Ordinary  em])hysemas 
of  the  skin  which  accompany  rib-fracture,  pulmonary  emphy- 
sema, or  wounds  (median  neurectomy,  trocaring,  intentional 
inflation  of  the  scapular  region  to  conceal  muscular  atrophies) 
are  not  attended  by  fever  and  comi)arati\'ely  benign  in  course. 
The  postmortem  emphysenia  noted  in  parenchymatous  organs 
in  delayed  necropsies  during  hot  weather  would  hardly 
mislead  a  careful  observer. 


BLACK-LEC,  287 

Course  and  Prognosis. — The  course  of  malignant  edema  is 
usually  rapid,  death  resulting  from  pulmonary  edema  in 
twenty-four  to  sixty  hours.  The  prognosis  is  bad,  95  per  cent, 
of  the  cases  die.  Recovery  can  be  expected  only  in  mild 
infections  and  when  proper  treatment  has  been  prompt. 

Treatment. — The  treatment  is  surgical,  and  consists  in 
slitting  the  swellings  long  and  deep  to  allow  oxygen  to  enter 
the  tissue.  A  thorough  disinfection  of  the  incisions  should 
follow  while  subcutaneous  injections  of  iodin  tincture  may  be 
made  in  the  neighborhood  of  the  swellings.  Hot  applications 
should  be  avoided. 

In  France,  Leclaniche  and  Valler  have  practised  preventive 
inoculations  with  attenuated  spores  from  edematous  fluid 
and  cultures.  Good  results  are  claimed.  Of  scientific  interest 
is  the  fact  that  such  inoculations  do  not  immunize  against 
black-leg. 

BLACK-LEG. 

Definition. — Black-leg  is  an  acute  infectious  disease  of 
young  cattle,  due  to  a  specific  bacillus  and  characterized  by 
fever  and  the  formation  of  emphysematous  swellings  involving 
muscular  groups  in  various  parts  of  the  body.  It  is  not 
directly  contagious. 

Occurrence. — While,  generally  speaking,  black-leg  has  a 
world-wide  distribution,  outbreaks  occur  usually  only  in 
certain  so-called  black-leg  districts.  In  this  respect  it  re- 
sembles anthrax,  with  which  it  was  long  confused.  In  the 
United  States  the  Western  States  suffer  most,  although 
sporadic  outbreaks  have  been  observed  in  the  Central  and 
Eastern  States.  The  Southern  Atlantic  and  Eastern  Gulf 
States  are  said  to  be  free.  In  some  of  the  Western  States 
(Kansas,  Dakotas,  Nebraska)  the  animal  losses  from  black- 
leg exceed  those  from  all  other  diseases  combined.  The 
worst  infected  area  on  this  continent  seems  to  be  that 
bounded  north  and  east  by  the  Missouri  and  Mississippi 
Rivers  and  west  by  the  Rocky  Mountains,  the  great  cattle 
country. 

Etiology. — The  Bacillus  gangra^nte  emphysematosse,  an 
anaerobe  which  occurs  in  soil,  water,  and  in  infected  districts 


288         ACUTE  GENERAL  INFECTIOUS  DISEASES 

in  thv  (ln)i)i)in<i;s  of  cattle.  Morphologically  and  culturally 
the  black-leg  bacillus  so  closely  resembles  the  malignant 
edema  bacillus  that  diflFerentiation  is  very  difficult. 

Natural  Infection. — (a)  Through  wounds  in  the  skin  and 
mucous  menibranes.  Stubble,  thorns,  spines,  barbed  wire, 
etc.,  causing  small  punctured  wounds,  which  on  account  of 
their  character  are  most  apt  to  become  infected  with  soil, 
etc.,  containing  the  rods  or  spores. 

(6)  Through  the  digestive  tract  from  the  ingestion  of  con- 
taminated food  and  water.  The  presence  of  the  black-leg 
tumor  in  the  tlii'oat,  bowels,  and  other  internal  organs,  and 
the  occurrence  of  outbreaks  in  stable-fed  animals  speak  for 
this  mode  of  infection.  The  disease  is  miasmic  and  does  not 
spread  from  animal  to  animal.  Black-leg  carcasses,  however, 
if  not  rendered  harmless  by  cremation  or  deep  burial,  con- 
tribute toward  the  perpetuation  of  the  infection  by  reinfecting 
the  soil. 

Symptoms. — Black-leg  is  seen  almost  exclusively  in  cattle. 
Probable  cases  in  sheep  and  swine  have  been  recorded.  Opin- 
ions differ  concerning  its  occurrence  in  horses,  but  no  authentic 
data  in  this  regard  are  available.  Black-leg  is  a  disease  of 
young,  full-blood,  or  high-grade  cattle.  It  is  rarely  noted  in 
animals  under  six  months  or  over  two  years  of  age.  The 
period  of  incubation  is  usually  one  to  three  days,  occasionally 
longer  (five  days).  The  symptoms  are  both  (a)  general  and 
(6)  local. 

General  Symptoms. — Fever,  the  temperature  reaching  107° 
F.,  refusal  of  food,  suspended  rumination,  and  great  mental 
depression.  Quite  often  the  first  symptom  noticed  is  lame- 
ness in  one  limb. 

Local  Sympfonis. — Following  or  sometimes  ])rece(ling  the 
general  symptoms,  external  swellings  a])pear  in  the  region  of 
the  thigh,  croup,  loins,  shoulder,  breast,  and  throat.  ^Vhilc 
at  first  small,  the  tumefactions  rapidly  increase  in  size  until 
a  large  portion  of  the  body  is  involved.  In  rare  cases  the 
swellings  may  be  internal  and  located  in  the  tongue  or 
])harynx  or  bowel  (colic  symptoms).  At  first  the  tumors  are 
firm,  hot,  and  tender,  but  later,  provided  the  animals  live 
long  enough,  cooler,  non-sensitive,  the  overlying  skin  hard 


BLACK-LEG  289 

and  dry,  and  on  palpation  marked  crepitation  is  noted.  When 
the  tumors  are  incised,  a  bloody,  foamy  fluid  of  a  peculiar 
sweetish,  fetid  odor  is  discharged.  The  periphery  and  en- 
vironment of  the  swelling  are  edematous.  The  lymph  glands 
are  swollen,  and  may  be  felt  under  the  skin  as  firm  nodes 
at  times,  the  size  of  a  goose  egg.  As  the  swellings  enlarge 
the  symptoms  become  more  pronounced,  the  patient  shows 
marked  dyspnea,  is  unable  to  rise,  muscular  tremors  and  even 
violent  convulsions  occur,  the  temperature  rapidly  falls,  and 
death  follows. 

Course. — The  course  is  rapid  and  fatal.  ^Nlost  patients  die 
in  from  twelve  to  forty-eight  hours.  Isolated  cases  may 
linger  several  days  (mild  invasion,  high  resistance),  then  die, 
or  in  rare  instances  recover. 

Diagnosis. — Black-leg  is  a  disease  easily  diagnosed,  pro- 
vided the  typical  swellings  are  in  evidence.  As  a  rule  the 
ovsiier  or  ranchman  recognizes  it  without  professional  aid.  If 
the  characteristic  emphysematous  enlargements  are  absent, 
however,  as  is  common  in  the  first  cases  of  some  out- 
breaks, a  diagnosis  intra  vitam  is  very  difficult.  Black-leg 
may  be  confused  with  malignant  edema  and  anthrax  (see 
these) . 

Necropsy. — The  cadaver  is  greatly  bloated  and  swollen, 
especially  about  the  tumors.  When  the  swellings  are  cut  into, 
a  foamy,  dark,  fluid  flows  out.  The  affected  muscle  is  of  a 
dirty  brown  to  blackish  color,  very  friable,  and  often  smells 
like  rancid  butter.  The  blood  is  dark  colored  but  coagulates 
readily.  In  the  serous  cavities  blood-stained  fluid  is  found. 
The  lymph  glands  corresponding  to  the  tumors  are  swollen 
and  blood-shot.  The  spleen  is  usually  normal.  The  charac- 
teristic postmortem  lesions  are:  normal  blood,  normal  spleen, 
and  emphysematous  swellings. 

Prognosis. — In  young  cattle  fully  98  per  cent.  die.  In  older 
individuals  a  few  recover. 

Treatment. — A  medicinal  treatment  is  useless.  Surgical 
intervention  as  recommended  in  malignant  edema  is  rarely 
advisable  except  in  very  valuable  individuals.  It  is  further- 
more a  menace,  as  the  discharge  from  the  incisions  spreads 
the  infection. 
19 


290         ACUTE  GENERAL  INFECTIOUS  DISEASES 

Prophylaxis. — When  an  outbreak  occurs  all  cattle  two  years 
old  and  under  should  be  ])roni|)tIy  removed  to  a  i)referably 
hii^her  and  drier  ])asture.  In  stable-fed  victims  a  chanfj;e  to 
known  uninfected  food  is  imperative.  The  dead  should  be 
disposed  of  as  recommended  under  Anthrax.  Exposed  ani- 
mals should  be  vaccinated  which  successfully  protects  ajjainst 
serious  infection.  Black-leg  vaccines  are  now  obtainable 
from  many  State  experiment  stations,  the  Bureau  of  Animal 
Industry,  and  several  commercial  houses  dealing  in  biological 
products. 

AyiMcation. — The  vaccine  is  administered  by  injecting  it 
under  the  skin,  the  patient  being  properly  secured.  Usually 
the  needle  is  inserted  in  the  thin,  loose  skin  just  in  front  of 
the  shoulder.  Previous  disinfection  is  not  necessary,  but  the 
needle  and  syringe  must  be  first  sterilized.  The  dose  will 
depend  upon  the  vaccine  used.  Cattle  may  be  vaccinated 
any  time  of  the  year.  Cattle  already  infected  should  not  be 
treated;  the  vaccine  has  no  curative  value.  Hiefers  in  ad- 
vanced pregnancy  should  not  be  vaccinated.  RevaccinatioA 
may  be  practised  with  safety  in  two  weeks.  The  immimity 
conferred  reaches  full  de\'elopment  in  eight  to  ten  days,  dur- 
ing which  time  the  patients  pass  through  the  negative  phase, 
and  are  therefore  more  susceptible  to  infection  than  if  they 
had  not  been  vaccinated.  The  immunity  lasts  from  twelve 
to  eighteen  months. 

BRAXY.     GASTROMYCOSIS  OVIS. 

Definition. — An  infectious  disease  of  sheep  characterized  by 
its  short,  fatal  course,  and  due  to  a  specific  anaerobic  bacillus 
resembling  the  black-leg  bacillus. 

Occurrence. — Braxy  has  not  yet  been  reported  in  the  I  nited 
States.  Tn  Norway,  Denmark,  Iceland,  (iermany,  and  Scot- 
land it  is  common,  leading  to  great  losses  among  yearling 
lambs.  The  disease  is  rarely  seen  in  suckling  lambs  or  in 
sheep  over  two  years  of  age.  While  sporadic  cases  may  occur 
during  the  summer  months  when  sheep  are  on  pasture,  serious 
outbreaks  take  place  during  the  late  fall  and  early  winter 
months  after  the  sheep  have  been  returned  to  the  fold  for 


BRAXY—GASTROMYCOSIS  OVIS  291 

the  winter.  Peculiarly,  outbreaks  seem  more  common  fol- 
lowing a  heavy  frost. 

Etiology. — Braxy  is  due  to  the  Bacillus  gastromycosis  ovis, 
an  anaerobe  which  usually  carries  a  spore  near  one  end,  pro- 
duces gas  and  stains  according  to  Gram.  The  germ  is  patho- 
genic to  guinea-pigs,  rabbits,  and  pigeons.  While  subcutane- 
ous inoculations  generally  produce  the  disease  in  susceptible 
sheep,  feeding  experiments  with  this  bacillus  have  given 
negative  results. 

Natural  Infection. — Probably  tlirough  wounds  (in  upper 
digesti^^e  tract?)  and  possibly  through  the  digestive  tract  with 
food.  The  disease  is  not  thought  to  be  spread  by  drinking 
water. 

Necropsy. — In  peracute  cases  few  if  any  postmortem 
changes  can  be  noted.  In  acute  cases  usually  the  principal 
lesions  are  found  in  the  abomasum  and  duodenum,  the  mucous 
membrane  of  which  is  swollen,  edematous,  and  spotted  with 
occasional  bluish-red  hemorrhagic  areas.  Necrotic  patches 
have  been  described.  The  blood  is  dark  but  readily  coagu- 
lates, and  the  spleen  not  enlarged.  The  liver  and  kidneys 
show  parenchymatous  degeneration.  In  the  body  cavities  a 
serohemorrhagic  exudate  collects  and  the  subcutaneous  con- 
nective tissue  is  edematous.  Decomposition  occurs  rapidly 
and  emphysema  of  the  parenchymatous  organs  is  commonly 
found  in  delayed  necropsies. 

In  the  diseased  mucous  membranes,  the  infiltrated  sub- 
mucosa,  in  the  fluid  of  the  body  cavities,  blood,  and  parenchy- 
matous organs  the  specific  germ  is  found. 

Symptoms. — The  period  of  incubation  is  two  or  three  days. 
The  course  of  braxy  is  so  rapid  and  fatal  that  clinical  symp- 
toms are  rarely  observed  by  the  veterinarian.  Even  in  those 
cases  which  may  be  examined  clinically  the  symptoms  are  not 
particularly  characteristic.  It  may  be  noted  that  the  affected 
sheep  are  restless,  alternately  lying  down  and  getting  up 
suddenly,  as  if  in  pain.  There  may  be  slight  bloating,  arched 
back,  and  pendent  head.  AYhen  artificially  injected  sub- 
cutaneously  the  injected  limb  is  dragged  behind.  The  sheep 
champs  the  jaws,  churning  the  saliva  into  foam.  It  usually 
leaves  the  rest  of  the  herd,  is  very  listless,  and  depressed.    In 


292         ACUTE  GENERAL  INFECTIOUS  DISEASES 

some  outl)reaks  diarrhea  is  an  early  syinjitoni.  The  tempera- 
ture is  elevated  (105°  to  108°  F)  and  the  respirations  dysi)neic. 
1  snally  after  a  couple  of  iiours  the  patient  falls  over,  becomes 
comatose,  and  dies. 

Diagnosis. — Braxy  is  often  confused  with  anthrax,  especially 
when  it  occurs  in  anthrax  districts.  It  might  also  ])e  mistaken 
for  black-leg  or  for  malignant  edema.  By  carefully  weighing 
the  history,  clinical  symptoms,  and  bacteriological  findings, 
error  in  diagnosis  is  avoided. 

Course  and  Prognosis. — The  course  is  rapid;  usually  in  from 
fifteen  to  eighteen  hours  the  patients  die.  The  prognosis  is 
bad;  fully  98  per  cent,  succumb. 

Treatment.— Medicinal  treatment  has  not  proved  of  value. 
Sejjaration  of  the  living,  deep  burial,  or  cremation  of  the  dead 
and  a  thorough  disinfection  of  the  barns,  pens,  yards,  etc., 
are  indicated. 

Protective  Inoculation. — Nielsen  and  Jensen  have  employed 
protective  inoculation  to  combat  braxy,  the  former  using 
dried,  powdered  kidney  substance  from  a  fatal  case,  while  the 
latter  used  either  treated  blood-serum  cultures  or  blood  serum 
from  artificially  immunized  horses  or  cultures  one  month  old 
which  were  grown  in  sugar  bouillon.  Apparently  good  results 
have  been  obtained  in  Iceland  with  preventive  vaccination 
(see  Bacteriology) . 

SWINE  ERYSIPELAS. 

Definition. — Swine  erysipelas  is  an  infectious  disease  due  to 
a  si)ecific  microorganism.  It  has  a  varied  course  and  aj)pears 
clinically  as  an  acute  septicemia,  a  secondary  skin  exanthema, 
or  a  chronic,  valvular  heart  disease. 

Occurrence. — On  the  continent  of  Europe  the  disease  is 
wide-s])read,  occurring  during  the  hot  months,  and  in  latter 
years  has  assumed  a  more  serious  form  than  formerly.  In 
(ireat  Britain  swine  erysipelas  is  a  benign  disease,  api)earing 
in  the  skin  form  and,  as  yet,  has  not  assumed  serious  propor- 
tions. To  date  it  has  not  been  reported  in  the  I  nited  States. 
In  the  so-called  ''diamond  disease,"  so  commonly  found  in 
American  abattoirs,  erysipelas  bacilli  have  not  yet  been 
determined. 


SWINE  ERYSIPELAS  293 

Etiology. — The  Bacterium  erysipelatis,  a  fine  bacillus  found 
in  the  acute  form  of  the  disease  in  the  blood,  skin,  and  Ijinph 
glands.  In  the  chronic  form  they  are  found  in  the  dis- 
eased tissue,  particularly  in  the  valvular  vegetations  in  the 
heart. 

Natural  Infection. — (a)  ^ia  the  mouth  with  food  and  water 
contaminated  with  the  feces  and  urine.  The  blood  and  flesh 
are  also  infectious. 

(6)  Ma  wounds.  The  disease  is  usually  first  introduced  by 
infected  hogs  or  by  apparently  healthy  "germ  carriers," 
swine  which  have  recently  recovered  from  erysipelas  but  still 
carry  germs  in  the  bowels  and  tonsils.  Fields  on  which  the 
bodies  of  dead  hogs  have  lain  or  were  not  buried  deep  enough 
or  where  the  feces  and  urine  of  diseased  animals  are  deposited 
are  most  dangerous  sources  of  infection.  The  disease  is  not 
directly  contagious,  but  is  disseminated  largely  tlirough  soil 
infection.  Hogs  from  three  months  to  one  year  are  most 
susceptible.  Sucklings  and  old  animals  are  usually  quite 
resistant. 

Necropsy. — In  the  acute  form  very  little  change  is  noted 
postmortem.  The  small  intestines  are  catarrhally  inflamed. 
Peyer's  patches  and  the  solitary  follicles  are  swollen  and  small 
ulcerations  are  noted.  The  spleen  is  somewhat  enlarged. 
Ecch^Taoses  and  petechise  are  prone  to  appear  in  the  mucous 
and  serous  membranes,  especially  in  the  epi-  and  endocardium 
and  in  the  subcutaneous  connective  tissue.  The  kidneys  are 
swollen,  and  on  section  the  cortex  is  grayish-red,  dotted  with 
punctiform  hemorrhages,  the  medullary  substance  dark.  As 
a  rule  the  lungs  are  not  involved.  In  chronic  cases  the  prin- 
cipal lesion  is  found  in  the  heart,  the  atrioventricular  valves 
showing  lesions  of  verrucous  or  ulcerous  endocarditis. 

Symptoms. — The  period  of  incubation  is  tlu-ee  to  five  days. 
The  cHnical  sjTnptoms  vary,  but  the  following  forms  are 
fairly  well  distinguished. 

(a)  Skin  Form. —  Urticaria  Type  ("Diamond  Diseasef"). 
— After  a  short  period,  during  which  the  hog  seems  languid 
and  fails  to  eat  well,  there  appear  in  the  skin  on  the  sides  of 
the  chest,  back,  neck  and  legs,  sometimes  all  over  the  body, 
violet-colored  spots  and  sometimes  vesicles.    The  spots  are 


294         ACUTE  GENERAL  INFECTIOUS  DISEASES 

often  rec'tanjijuljir  or  rlioinboid  in  form  and  are  elevated  above 
the  surroundinji;  skin.  'i^lu\\'  are  usnally  ahont  the  size  of  a 
r)()-cent  piece,  hir^er  l)y  conHnence.  Sometimes  vesicles  occnr 
upon  them  which  break,  the  discharge  drying  to  brownish 
crusts.  As  a  rule  symptoms  of  fever,  languor,  anorexia,  con- 
stipation, paraplegia,  conjunctivitis,  and  vomiting  attend  the 
exanthema.  The  skin  eru})tion  usually  disapj)ears  in  from  one 
to  two  weeks.  In  some  cases  necrosis  of  the  skin,  especially 
of  the  ears,  tail,  or  digits  takes  place,  leading  to  sloughing 
and  healing,  with  pronounced  scar  formation. 

(b)  Septicemia  Form. — This  form  very  much  resembles  the 
septicemia  (explosive)  form  of  hog  cholera  (see  this).  The 
skin  is  usually  highly  reddened,  especially  on  pendent  portions 
of  the  body.  The  red  colorations  have  an  erythematous  char- 
acter, finger  pressure  temporarily  removing  them.  Vesicle 
formation  and  necrosis  may  also  occur.  In  severe  cases  there 
is  paraplegia,  cyanosis,  and  great  dyspnea  (lung  edema).  The 
patients  usually  die  in  three  or  four  days  or  may  live  a  week. 
In  some  cases  the  symptoms  subside  on  about  the  third  day, 
the  animal  reco^'ering  or  the  disease  assuming  the  chronic 
form. 

(c)  Chronic  Form. — In  this  type  symptoms  of  chronic 
endocarditis  (see  this)  and  gangrene  of  the  skin  occur.  It  is 
noted  in  hogs  which  have  passed  through  the  acute  stage  and 
seem  to  be  recovering.  In  about  one  or  t^^■o  months,  however, 
they  begin  to  droop,  lose  appetite,  cough,  become  dyspneic, 
cyanotic,  develop  heart  ])alpitation  ("thumps"),  and  carry 
a  mild  fever.  (Gradually  becoming  weak,  after  several  weeks 
the>'  die  of  inanition. 

Prognosis. — The  skin  form  is  benign,  ])ractically  all  recover- 
ing. In  the  septicemic  form  the  mortality  is  (>()  to  90  per  cent, 
and  chronic  cases  are  generally  fatal. 

Diagnosis. — Swine  erysipelas  is  easily  confused  witli  hog 
cholera.  ( linically  the  differences  are  not  marked.  As  a  rule, 
however,  the  lungs  and  bowels  are  less  afi'ected  in  erysipelas 
and  the  reddening  of  the  skin  is  intra-  rather  than  extra- 
v^ascular.  Bronchopneimionia  with  pleiu'itis  and  button-like 
ulcers  in  the  cecum  or  necrosis  of  the  intestinal  nuicous  mem- 
brane are  lesions  not  seen  in  swine  erysipelas.     In  (l()ul)tful 


HEMORRHAGIC  SEPTICEMIA  295 

cases  a  bacteriological  examination  of  the  blood  should  be 
made. 

Treatment. — A  medicinal  treatment  is  useless. 

Prevention. — As  the  bacillus  of  this  disease  has  a  saprophytic 
existence  in  soil,  and  is  often  present  in  the  tonsils  and  bowels 
of  "germ  carriers,"  it  is  difficult  to  eradicate.  However,  the 
usual  causes  of  infection,  as  noted,  are  affected  swine,  living 
or  dead,  and  therefore  susceptible  hogs  should  be  isolated 
from  them.  Infected  pens  and  hog  lots  should  be  thoroughly 
disinfected,  the  droppings  collected  and  rendered  innocuous. 
Hog  pastiu-es  contaminated  with  the  germs  should  be  culti- 
vated.   Carcasses  shoidd  be  burned  or  buried  deep. 

Protective  Inoculation. — As  one  attack  of  erysipelas  pro- 
duces immunity,  vaccination,  much  practised  in  Europe,  is 
feasible.  Two  methods  are  employed:  one  known  as  that  of 
Pasteur,  which  requires  a  double  vaccination,  the  first  fol- 
lowed by  a  second  in  twelve  days;  the  other  is  known  as 
the  simidtaneous  (serimi  and  cultures  together)  method  of 
Lorenz  and  of  Laclaniche,  which  also  requires  that  the 
vaccination  be  once  repeated. 


HEMORRHAGIC  SEPTICEMIA.     PASTEURELLOSIS. 

Under  the  collective  term  "hemorrhagic  septicemia"  is 
gathered  a  group  of  diseases  characterized  by  general  septi- 
cemic infection  (blood  spots  appearing  in  the  skin,  serous 
membranes,  bones  and  joints),  and  in  the  tissues  one  of  the 
varieties  of  a  belted  or  coco  bacillus  known  as  the  Bacterium 
bipolaris  septicum  or  the  Bacterimn  Pasteurella. 

Under  this  head  are  usually  included  the  following  diseases : 
chicken  cholera,  rabbit  septicemia,  hemorrhagic  septicemia  of 
cattle,  septic  pneumonia  of  calves,  the  buffalo  plague,  hemor- 
rhagic septicemia  of  sheep,  takosis  of  goats  (?),  swine  plague, 
and  enzootic  pneimionia  of  shoats. 

At  the  present  time,  for  lack  of  sufficient  experimental  data, 
it  is  difficult  to  decide  just  what  relationship  the  bipolar  bac- 
teria bear  to  the  diseases  they  are  supposed  to  cause.  The 
fact  that  the  bipolar  bacilli  are  found  in  the  tissues  and  body 


29G         ACUTE  GENERAL  INFECTIOUS  DISEASES 

fluids  after  death  is  not  i)ro()f  that  they  were  the  i>riinary 
cause  of  the  disease  present.  Furthermore,  they  are  not 
infre([uently  met  with  in  animals  whieli  showed  no  symj)toms 
of  disease.  Before  the  discovery  and  use  of  the  Dorset  serum, 
to  prevent  cholera  in  hogs,  the  now  pectoral  form  of  this 
disease  was  considered  by  nearly  every  authority  to  be  a 
separate  and  distinct  malady,  and  known  as  "swine  plague." 
Notwithstanding  the  fact  that  so-called  "swine  plague"  was 
clinically  associated  with  practically  all  cholera  outbreaks, 
provided  they  lasted  long  enough,  and  usually  formed  part  of 
the  lesions  on  examining  the  cholera  carcass,  the  unity  of  the 
conditions  was  not  admitted.  With  the  introduction,  how- 
ever, of  a  succ-essful  pre\'entive  treatment  for  cholera,  based 
upon  an  ultramicroscopic  organism  as  the  etiological  factor,  it 
was  soon  recognized,  as  both  diseases  were  equally  protected 
against,  that  in  all  i)r()bability  the  bipolar  bacillus  was  merely 
a  secondary  invader.  It  is  quite  i)()ssible  that  further  experi- 
ment, which  is  nnich  desired,  will  show  that  the  relationship 
of  the  bipolar  bacillus  to  the  other  diseases  of  this  group  will 
be  similar  to  that  experienced  in  hog  cholera.  For  the  present, 
however,  and  until  further  reliable  data  are  available,  the 
varieties  of  the  })actcrium  may  be  considered  etiological 
factors  in  the  remaining  diseases  of  this  group. 

Hemorrhagic  Septicemia  of  Cattle  {Corufttalk  Disease, 
Bronc'hopDciunouui.  (iaiiic  and  Caiflc  I'lafiiie).- — Definition.- — 
Hemorrhagic  sej^ticcmia  is  a  fatal,  infectious  disease  of  cattle, 
having  an  acute  or  sul)acute  course,  which  assumes  a  variety 
of  forms  in  that  it  may  involve  the  nervous  system,  skin, 
lungs,  and  bowels.  It  is  probal)ly  caused  by  the  Bacterium 
bovisepticum. 

Occurrence. — The  disease  is  widely  si)read,  occurring  in  all 
parts  of  the  world.  In  the  Ignited  States  it  has  been  reported 
from  all  sections,  but  seemingly  is  more  prevalent  in  the  West 
and  Northwest  than  elsewhere.  Several  outl)reaks  have 
occurred  in  Ohio.  Besides  cattle  it  attacks  wild  animals, 
especially  deer. 

Etiology.  The  Bacterium  bovisepticum,  a  variety  of  the 
coco  bacillus,  is  found  in  soil  and  water  and  in  the  respiratory 
organs  of  apparently  healthy  cattle. 


HEMORRHAGIC  SEPTICEMIA  297 

Natural  Infection. — (a)  Via  digestive  tract,  the  germs  being 
taken  in  with  the  food  and  water. 

(6)  Jia  wonnds  through  the  skin  and  mucous  membranes. 

(c)  Via  respiratory  organs  (proved  in  rabbits).  The  hides 
and  flesh  of  infected  animals  spread  the  disease.  The  blood 
in  the  later  stages  is  infectious  and  probably  the  feces  and 
urine. 

Necropsy. — Varies  somewhat  with  the  type,  but  the  fol- 
lowing lesions  are  fairly  constant:  A  marked  congestion  of 
the  parenchymatous  organs.  Subcutaneous,  submucous,  and 
subserous  hemorrhages  generally  distributed  along  the  bowels 
(serous  surface),  over  the  spleen  capsule,  kidneys,  bladder, 
diaplu-agm,  peri-  and  epicardium,  s>'novial  membranes,  and 
meninges.  The  heart,  liver,  and  kidneys  show  cloudy  swell- 
ing. The  spleen  is  not  enlarged.  The  urine  is  sometimes 
blood-tinged.  In  the  skin  (exanthema tons)  form  the  subcutis 
of  the  region  of  the  throat  and  neck  shows  gelatinous  infiltra- 
tion spotted  with  blood  patches.  The  mucous  membranes  of 
the  digestive  tract  are  swollen  and  show  petechia?.  The 
tongue  is  swollen,  and  submucous  infiltrations  are  noted  in 
the  pharynx  and  larynx.  The  bowel  contents  are  usually 
semiliquid  and  frequently  chocolate  colored.  Blood  appar- 
ently normal.  In  the  pectoral  form  serofibrinous  pleiu'itis 
with  bronchopneumonia  is  found.  The  interlobular  septa  are 
markedly  infiltrated,  forming  broad,  yellow  strands.  Blood 
extravasations  occur  under  the  pleiu*a. 

Symptoms. — The  period  of  incubation  is  short,  usually  one 
or  two  days.  The  s\inptoms  are  not  particularly  character- 
istic and  quite  varied,  depending  upon  whether  or  not  the 
intestinal,  exanthematous,  or  pectoral  is  present. 

Intestinal  Form. — The  animal  appears  dull  and  shows  a 
staggering  gait  and  loss  of  sensitiveness  in  the  skin;  in  some 
cases  the  neck  is  bent  to  one  side  (torticollis),  the  muscles  of 
the  neck  and  jaw  twitcliing;  nystagmus  is  also  seen.  Occa- 
sionally forced  movements  are  noted,  the  patient  rapidly 
wheeling  in  a  circle,  using  the  hind  feet  as  a  pivot  (clock-hand 
movements).  During  these  paroxysms,  which  occur  inter- 
mittently, the  patient  may  utter  lowing  cries.  Diarrhea  may 
or  may  not  be  present.    There  is  drooling  from  the  mouth  and 


298         ACUTE  GENERAL  INFECTIOUS  DISEASES 

a  persistent  nervous  elianipin<;-  of  the  jaws.  The  tongue  is 
swollen  and  cyanotic.  High  fever  is  noted,  in  some  case.s  the 
temperature,  especially  after  a  ner\'()us  paroxysm,  reaching 
108°  F.  and  over.  Some  authorities,  however,  have  found 
the  temperature  normal  or  even  subnormal. 

Exanthenudous  Form. — This  form  is  less  frequent  in  Amer- 
ican outbreaks.  Inflammatory  edema  of  the  head,  neck, 
throat,  and  dewlaj)  appear.  The  swellings  may  extend  to  the 
body  and  limbs.  They  are  pronouncedly  hot  and  painful. 
Conjunctivitis  with  profuse  lacrimosis  may  be  present.  The 
tongue  is  edematously  swollen,  filling  the  whole  mouth  cavity, 
and  is  cyanotic.  Drooling  is  noted.  The  patient  is  dyspneic, 
the  mucous  membranes  dark  colored  and  show  petechia^. 
Death  results  from  asphyxia  or  severe  enteritis.  Intestinal 
symptoms  are  commonly  noted  in  this  form. 

Pectoral  Form. — The  symptoms  of  this  form  are  those  of  an. 
acute  or  subacute  l)ronchoi)neumonia  with  pleuritis.  The 
patients  stand  with  arched  back,  have  a  painful  cough  and 
nasal  discharge.  Dulness  is  noted  on  percussion.  Bronchial 
sounds,  rales,  and  rhonchi  are  heard  on  auscultation.  The 
patient  is  dyspneic,  appetite  is  lost,  and  rumination  suspended. 
The  constipation  is  later  followed  by  diarrhea,  inanition,  and 
death. 

Differential  Diagnosis.— Hemorrhagic  septicemia  might  be 
confused  with  anthrax,  Rinderpest  and  the  subacute  or 
chronic  pectoral  form  with  contagious  pleuropneumonia  of 
cattle.  It  might  also  resemble  black-leg.  The  absence  of 
splenic  enlargement,  the  normal  ai)pearance  of  the  blood,  and 
the  absence  of  the  anthrax  bacillus  ditt'erentiate  it  from 
anthrax.  Rinderi)est  does  not  occur  in  the  United  States, 
but  is  found  in  the  Philippines.  Outbreaks  of  Rinderpest  can 
usually  be  tracetl  to  an  imported  source  (diseased  cattle), 
and  in  this  disease,  unlike  hemorrhagic  septicemia,  a  marked 
ulcerous  inflammation  of  the  mucous  membrane  of  the  eye- 
lids, respiratory  and  digestive  tract  is  present.  Contagious 
pleuropneumonia  no  longer  exists  in  this  country.  ]\Iacro- 
scopically  the  lesions  of  the  pectoral  form  of  hemorrhagic 
septicemia  and  this  disease  may  be  almost  identical.  In  such 
cases  only  the  use  of  bacteriological   nicthods  can  decide 


HEMORRHAGIC  SEPTICEMIA  299 

(findinji;  the  bipolar  bacterium;  animal  inoculations).  In 
typical  cases  of  black-leg  there  should  be  no  difficulty  in 
dirt'erentiation,  as  emphysematous  surface  swellings  are  not 
seen  in  hemorrhagic  septicemia.  Furthermore,  the  latter  dis- 
ease affects  cattle  of  all  ages  while  black-leg  is  essentially  a 
disease  of  young  animals  (see  this). 

Course. — The  course  varies  with  the  form  the  disease 
assumes,  the  severity  of  the  infection  and  the  resistance  of 
the  individual  patient.  Acute  cases  last  only  a  few  hours 
(6  to  20)  while  less  acute  ones  may  linger  a  week  or  even 
longer.  Those  affected  with  the  lung  form  usually  live  longer 
than  in  the  intestinal  or  exanthematous  forms  of  the  disease. 

Prognosis. — Very  bad.    Fully  90  per  cent.  die. 

Treatment. — ^Medicinal  treatment  is  useless.  In  outbreaks 
removing  the  sick  cattle  to  other  pastures  is  recommended. 
If  the  disease  occurs  in  a  stable,  disinfection  is  in  place.  As 
a  rule,  after  a  certain  number  of  cattle  in  a  herd  die  the  disease 
stops  of  itself.  The  carcasses  should  be  disposed  of  as  recom- 
mended under  Anthrax.  The  dried  hides  are  said  to  be 
harmless. 

Septic  Pleuropneumonia  of  Calves.— Definition. — This  dis- 
ease is  evidently  a  form  of  hemorrhagic  septicemia  of  cattle. 
It  is  a  specific  pleuropneumonia  of  calves  due  to  a  bipolar 
bacillus. 

Occurrence. — ^The  disease  is  widely  distributed  and  not 
infrequently  occurs  simultaneously  with  an  outbreak  of 
hemorrhagic  septicemia  of  older  cattle. 

Etiology. — The  Bacterium  vitulisepticum  which  seems  iden- 
tical with  the  germ  Bacterium  bovisepticum. 

Natural  Infection. — Infection  takes  place  tlu-ough  the  di- 
gestive tract,  with  food  and  water  polluted  with  the  discharge 
of  affected  calves. 

Necropsy. — The  principal  changes  are  bronchopneumonia 
with  serofibrinous  pleuritis.  Catarrhal  bronchitis  and  laryn- 
gitis are  also  present.  Gastro-intestinal  catarrh,  swelling  of 
the  lymph  glands,  and  cloudy  swelling  of  the  parenchymatous 
organs  attend. 

Symptoms. — The  symptoms  are  those  of  acute  or  subacute 
pneumonia.     The  affected  calves  are  listless,  the  hair  coat 


30n         ACUTE  GENERAL  INFECTIOUS  DISEASES 

stariiifj;,  mu/z/lo  dry,  ahdoiueii  tucked  up  aud  the  goiicral 
appearance  unthrifty.  A  common  symptom  is  a  short,  some- 
what })ainful  coufijh  emitted  when  the  animals  are  disturbed 
or  driven  from  the  barn  into  the  outsi(k^  air.  The  appetite 
may  be  retained.  The  temperature  is  elevated  and  the  res- 
pirations d\'spneic.  Palpation  over  the  thorax  induces  pain. 
On  percussion  there  is  dulness  in  the  lower  part  of  the  chest, 
and  on  auscultation  either  the  sounds  of  breathing  are  absent 
or  bronchial  tones  may  be  heard.  More  rarely  friction  sounds 
are  evident.  The  patients  gradually  become  weaker,  and  in 
most  cases  either  die  in  one  or  two  weeks,  or  there  develops 
chronic  pulmonary  phthisis. 

Prognosis. — The  ])rognosis  is  uncertain;  the  mortality  varies 
but  a\'erages  about  50  per  cent. 

Treatment.^ — The  medicinal  treatment  is  symptomatic,  as 
recommended  in  pneumonia.  Tt  is  advisable  to  separate  the 
affected  animals  from  the  healthy,  to  bury  deep  or  cremate 
the  dead,  and  thoroughly  disinfect  the  barns  and  premises. 
As  a  prophylactic  measure,  inoculating  the  calves  with  blood 
serum  derived  from  an  artificially  immunized  horse  treated 
with  cultures  of  the  bipolar  bacillus  has  been  practised  with 
apparent  success. 

Hemorrhagic  Septicemia  of  Sheep. — Definition. — Hemor- 
rhagic septicemia  of  sheep  manifests  itself  in  acute  cases  as  a 
general  septicemia.  In  subacute  and  chronic  cases  it  is  char- 
acterized by  nasal  and  eye  discharge,  also  by  pleuropneu- 
monia.   It  is  caused  by  the  Bacterium  ovisepticum. 

Occurrence. — The  disease  occasions  among  lambs  consider- 
able loss.  Older  sheep  are  rarely  attacked,  and  in  them  the 
disease  assumes  a  chronic  form.  Hemorrhagic  sejjticemia  of 
sheep  is  most  common  in  low,  damj),  marshy  regions.  It  is 
rare  on  high,  dry  land.  Outbreaks  occur  most  generally  at 
the  time  the  lambs  are  weaned. 

Etiology.  The  HacteriuuT  ovise})ticum,  a  variety  of  the 
Bacterium  bi])olaris  septicus.  It  is  difficult  to  cultivate  out- 
side of  the  body,  as  it  is  very  apt  to  die  in  cultures. 

Natural  Infection.^ — Through  the  digestive  tract,  the  sheep 
taking  in  infected  food  or  water  found  on  the  pastures  or  in 
contaminated  sheepfolds.    Young  sheep  at  w^eaning  tinie  are 


HEMORRHAGIC  SEPTICEMIA  301 

most  predisposed,  and  in  them  the  disease  assumes  usually  a 
very  acute  form.    In  older  sheep  the  disease  is  more  chronic. 

The  infective  discharges  of  diseased  animals  obviously  con- 
tribute toward  the  spread  of  the  disorder.  In  sheep  herds 
running  in  small  pastures  or  kept  crowded  in  folds  the  disease 
assumes  a  very  virulent  form.  It  is  transmitted  to  healthy 
sheepfolds  by  infected  animals. 

Predisposing  causes  are  anything  that  will  reduce  the  resis- 
tance of  the  sheep,  such  as  cold,  getting  wet  by  rain,  etc.  The 
disease  is  more  common  in  wet  seasons  and  on  low  grounds. 

In  all  probability  infection  with  strongyls  may  be  a  predis- 
posing cause. 

Necropsy. — In  peracute  cases  the  postmortem  is  largely 
negative,  except  for  the  s\'mptoms  noted  under  Hemorrhagic 
Septicemia . 

In  the  acute  form  the  subcutaneous  connective  tissue  of  the 
dewlap,  neck,  and  throat  shows  gelatinous  infiltration.  The 
mucous  membranes  of  the  head,  air  passages,  abomasum,  and 
bowel  are  inflamed  (reddened  and  swollen).  The  hmph 
glands  are  enlarged,  diffusely  reddened  (blood-shot).  Pete- 
chia and  ecchjTnoses  are  noted  in  the  serous  membranes, 
kidneys,  and  hmph  glands.  In  many  cases,  even  in  the  acute 
form,  the  lungs  are  involved.  In  them  are  found  dark,  red- 
dish-broAAii  areas  of  bronchopneumonia  surrounded  by  infil- 
trated interlobular  connective  tissue.  The  spleen  is  usually 
normal. 

In  the  subacute  form  bronchopneumonia  involving  the 
anterior  and  lower  parts  of  the  lung  is  present.  The  pleura 
and  also  the  pericardium  is  often  covered  with  fibrinous 
pseudomembranes  and  the  serous  cavities  partially  filled  with 
a  clear  yellow  or  turbid  fluid.  Bronchitis  and  enteritis  may 
also  be  present  and  in  many  cases  fibrinous  rhinitis. 

In  the  chronic  form  larger  areas  of  the  lung  and  pleura  are 
involved.  Thickenings  and  adhesions  are  common.  The  in- 
volved area  is  hepatized,  some  areas  which  have  undergone 
necrosis  sin-rounded  by  connective-tissue  capsules.  The 
necrotic  foci  when  cut  tlirough  show  a  yellow  centre  of  viscid 
pus  surrounded  by  concentric  layers  resembling  in  structure 
an  onion.    However,  in  some  cases  none  of  the  internal  organs 


302         ACUTE  GENERAL  INFECTIOUS  DISEASES 

show  marked  pathological  changes.  There  are  in  such  only 
the  symptoms  of  a  severe  pnenmonia  and  cachexia. 

Symptoms.-  In  the  acute  form,  which  usually  lasts  two  to 
hve  days,  or  even  a  shorter  period,  there  are  symptoms  of  a 
severe  feverish  disease.  The  lambs  are  very  dull,  stupid, 
refuse  to  eat,  show  increased  thirst,  dyspnea,  colic  symptoms, 
and  twitchings  of  the  muscles.  The  temi)eratin'e  is  often 
105.8°  F. 

In  subacute  cases  the  animal  may  li\e  one  to  three  weeks, 
during  which  time  it  shows  symptoms  of  fever,  poor  appetite, 
and  languor,  with  mucopurulent  discharge  from  the  eyes  and 
nose  In  some  instances  there  are  symptoms  of  pleuropneu- 
monia; in  others  enteritis  with  a  discharge  of  a  yellowish- 
green,  later  darker  colored,  fetid  feces.  In  some  cases  nodules 
and  also  ulcers  are  noted  on  the  mucous  membrane  of  the  lips 
and  cheeks.  Caries  of  the  teeth  may  occur.  The  lips,  cheeks, 
and  tongue  are  swollen  and  cyanotic.  In  rare  instances 
ulcerous  keratitis  has  been  observefl.  The  lambs  are  very 
weak  and  die  under  symptoms  of  cachexia.  In  rare  instances 
after  a  long  time  improvement  follows.  Complete  recovery 
is,  however,  rare.  As  a  rule  the  animals  are  stunted  by 
chronic  pneumonia  and  resulting  cachexia. 

The  chronic  form  is  seen  usually  only  in  adult  sheep. 
Sometimes  it  develops  from  the  acute  form.  The  symptoms 
are  those  of  a  severe,  chronic  pneiunonia.  The  sheej)  cough, 
show  dyspnea,  moderate  mucoi)urulent  nasal  and  eye  dis- 
charge, and  gradual  emaciation.  In  some  cases  there  develoj) 
swellings  of  the  carpal  and  tarsal  joints  and  purulent  inflam- 
mation of  the  hoof  matrix.  In  most  cases,  howe\'er,  the 
symptoms  are  those  of  a  general  cachexia. 

In  some  districts  in  which  this  infection  prevails,  coinci- 
dentally  animal  parasitism  is  assr)ciated  with  the  disease 
(strongyls,  tapeworms,  liver  flukes). 

Diagnosis. — The  acute  cases  might  be  confused  with  an- 
thrax. However,  the  normal  spleen,  absence  of  gelatinous 
blood  extravasations,  and  hematuria  usually  suffice  for  dif- 
ferentiation. Subacute  and  chronic  cases  so  much  resemble 
the  lung  and  stomach-worm  plague  of  lambs  that  diil'erentia- 
tion  would  be  very  difHcult  ])rovide(l  parasites  were  found. 


HEMORRHAGIC  SEPTICEMIA  303 

Braxy  affects  yearling  sheep  in  the  fall  and  winter  months. 
It  is  characterized  by  its  rapid,  fatal  course  and  the  hemor- 
rhagic areas  in  the  abomasum  and  duodenum  found  on 
necropsy.  Icterohematuria  of  sheep  presents  on  postmortem 
besides  icterus,  hemorrhagic  inflammation  of  the  abomasum., 
duodenum  and  rectum,  enlargement  of  the  spleen,  the  pulp  of 
which  contains  large  numbers  of  the  Piroplasmosis  ovum. 

Treatment  and  Prevention. — IMedicinal  treatment  is  largely 
useless.  A  slaughter  of  all  sheep  chronically  affected  is  recom- 
mended. The  sheep  should  be  removed  from  infected  pastures 
and  a  thorough  disinfection  of  the  sheepfold  should  follow. 
As  animal  endoparasites  probably  facilitate  the  bacterial  in- 
fection, the  sheep  should  not  only  be  kept  rid  of  worms,  but 
kept  from  worm-brood  infested  pastiu-es. 

Protective  Inoculation.— Good  results  were  obtained  in 
Argentine  by  the  use  of  a  polyvalent  \'accine  of  which  lambs 
were  given  each  \  c.c.  injected  subcutaneously.  Polyvalent 
immunizing  serum  was  also  effective. 

In  several  herds  of  infected  lambs  the  serum  of  the  horse 
which  had  been  hyperimmunized  with  cultures  of  the  Bac- 
terium ovisepticum  proved  of  practical  value.  The  serum  was 
given  simultaneously  with  the  vaccine.  In  these  experiments, 
as  the  immunity  lasted  only  six  weeks,  a  second  inoculation 
with  vaccine  is  recommended  at  the  end  of  one  month.  This 
simultaneous  method  proved  efficacious  in  that  it  stopped  the 
spread  of  the  disease  and  in  most  cases  healed  lambs  already 
infected. 

Takosis  of  Angora  Goats. — Definition. — Takosis  is  a  chronic 
contagious  disease  of  Angora  goats  characterized  by  weak- 
ness, emaciation,  diarrhea,  and  pneumonia,  which  leads  to 
death  in  from  one  to  eight  weeks. 

Occurrence.^ — The  disease  is  not  uncommon  in  the  United 
States,  particularly  in  the  Northern  States  (Oregon,  Missouri, 
Massachusetts,  Virginia  and  Maryland).  As  the  disease  is 
fatal,  and  30  to  85  per  cent,  of  the  goats  in  a  herd  are  attacked 
during  an  outbreak,  it  attains  considerable  economic  impor- 
tance. 

Etiology. — The  cause  seems  to  be  a  micrococcus,  the  Micro- 
coccus caprinus,  which  is  pathogenic  for  goats,  chickens,  rab- 


304         ACUTE  GENERAL  INFECTIOUS  DISEASES 

bits,  guinea-pigs,  and  white  mice,  i)ut  not  for  sheep,  dogs,  or 
rats. 

Necropsy. — The  necropsy  shows  evidence  of  general  anemia. 
In  tile  serous  membranes  petechite  are  found.  In  the  hmgs 
centres  of  pneumonia  are  present  and  in  the  pericardium 
accumulations  of  transudate.  There  is  chronic  catarrh  of  the 
mucous  membranes,  and  occasional  areas  of  necrosis  have 
been  noted. 

Symptoms. — The  symptoms  of  takosis  are  very  similar  to 
those  following  a  parasitic  invasion.  In  general  there  are 
emaciation,  weakness,  with  symptoms  of  diarrhea  and  cough. 
In  the  early  stages,  except  for  a  slight  weakness,  no  s\Tnptoms 
are  observable.  Later  the  afi'ected  goat  becomes  listless  and 
languid,  lags  behind  the  flock,  holds  its  head  low,  and  the 
eyelids  partially  closed.  There  is  usually  some  nasal  discharge 
and  occasional  coughing.  The  pulse  is  slow  and  weak,  the 
temperature  at  first  elevated  (104.1°  F.)  but  later,  a  few  hours 
before  death,  it  becomes  subnormal  (99.7°  F.).  As  the  disease 
progresses  the  gait  becomes  staggering,  the  back  arched, 
the  patient  moving  in  a  wavering,  unsteady  fashion.  The 
appetite  is  ca])rici()us.  Uumination  is  rarely  imi)aired.  The 
mucous  membranes  are  anemic,  the  respirations  increased. 
Finally  the  patient  becomes  so  weak  that  it  falls  to  the  ground 
and  must  l)e  assisted  to  its  feet,  (iradually  losing  Aveight,  it 
lingers  from  day  to  day,  and  finally  under  symptoms  of  fetid 
diarrhea,  succumbs.    Frequent,  ])laintive  bleating  is  noted. 

Diagnosis.-  The  symptoms  of  takosis  are  usually  so  similar 
to  those  of  parasitism  that  from  the  clinical  aspects  alone  a 
diagnosis  would  hardly  be  j)ossible.  The  necropsy  would 
determine  the  ])resence  or  absence  of  parasites.  However,  in 
parasitism  the  pneumonic  symptoms  are  not  so  well  developed 
and  the  tendency  for  submaxillary  edemas  to  form  is  greater. 

Course. — The  course  is  usually  chronic,  the  patient  dying  in 
from  one  to  eight  weeks.  The  mortality  is  100  per  cent. 
Pregnant  does  usually  abort. 

Treatment. — Medicinal  treatment  has  proved  unsatisfac- 
tory, as  all  patients  naturally  infected  die.  Some  authorities 
recommend  small  doses  of  calomel  (gr.  ij  twice  daily  for  two 
days)  followed  by  arsenic,  iron,  :iiid  (ininin: 


DISEASES  OF  NEWBORN  ANIMALS  305 

I^ — Arsen.  acid gr.  xx 

Ferri  reduct 3iv 

Quinin  sulph 5iss 

M.  f.  Pulv.  no.  XX. 
S. — One  powder  morning  and  evening. 

Prophylaxis. — To  prevent  takosis  it  is  recommended  that 
when  goats  are  shipped  from  one  part  of  the  country  to 
another  that  it  be  done  during  the  summer  or  late  spring, 
and  not  in  the  fall  or  winter,  thus  avoiding  as  far  as  possible, 
sudden  climatic  changes.  It  is  also  advisable  at  all  times  to 
provide  the  goats  with  a  storm  shelter  to  which  they  go 
voluntarily  during  a  downpour  of  rain.  That  the  herd  should 
be  given  proper  food  and  careful  attention  is  obvious. 

Once  the  disease  has  made  its  presence  in  a  flock  the  separ- 
ation of  the  sick  and  the  healthy  coupled  with  a  thorough 
disinfection  of  the  premises  are  indicated. 

SEPTICEMIC  DISEASES  OF  NEWBORN  ANIMALS. 

Dysentery  of  Sucklings  (Dysenteria  Neonatorum). — Defini- 
tion.— This  is  an  acute,  gastro-enteritis  rarely  occurring  in 
animals  over  one  week  old.  It  appears  enzootically  and  is 
characterized  clinically  by  a  profuse  diarrhea,  great  exhaus- 
tion, and  a  rapid,  fatal  course. 

Occurrence. — The  disease  occurs  in  calves,  lambs,  foals,  and 
pigs  (rare  in  dogs  and  cats)  and  appears  especially  in  breeding 
districts  at  the  time  of  parturition  (spring  and  fall),  causing 
great  losses  on  account  of  its  rapid  spread  and  fatal  termina- 
tion. In  some  outbreaks  every  calf  or  Iamb  born  on  the  prem- 
ises becomes  infected  and  dies  of  the  disease  in  the  first  few 
days  of  its  extra-uterine  life. 

Etiology. — The  Bacillus  coli  communis  or  some  of  its  varie- 
ties. Feeding  experiments  and  rectal  injections  of  colon 
bacilli  obtained  from  victims  of  the  disease  reproduce  it  in 
calves  of  susceptible  age.  It  is  possible  that  other  bacteria 
may  be  contributory  causes.  The  Bacillus  enteriditis  of 
Gartner  and  the  Bacillus  pyocyaneus  of  Poels  are  accused. 

Natural  Infection. — Once  introduced  into  a  barn  the  infec- 
tion remains  there  with  remarkable  tenacity,  causing  year 
20 


3UG         ACUTE  GENERAL  INFECTIOUS  DISEASES 

after  year  new  out])reaks  of  the  disease.  It  is  possible  for  this 
dysentery  to  de^'elop  in  a  stable  without  being  imported. 
This  is  probably  due  to  colon  bacilli,  which  are  li\'ino:  as 
saprophytes  on  the  premises,  assuming  a  virulent  form  once 
introduced  into  the  bodies  of  calves  with  lowered  resistance 
(bad  sanitation,  improper  feeding) .  The  infesting  germs  may 
enter  the  body:  (o)  via  navel  cord  or  {h)  via  digestive  tract. 
Calves  are  often  attacked  before  they  have  suckled  their 
dams.  An  intra-uterine  infection  seems  to  be  proved  by  the 
fact  that  an  injection  of  a  virulent  culture  of  the  colon  bacillus 
into  the  jugular  vein  of  a  pregnant  cow,  was  followed  in  eight 
days  by  the  birth  of  a  calf  with  the  disease.  Removing  the 
pregnant  dam  to  a  non-infected  place  does  not  always  protect 
her  young  from  infection.  Calves  which  have  not  yet  sucked 
seem  most  predisposed;  and  resistance  against  infection  in- 
creases as  the  calf  becomes  better  nourished  through  its 
natural  food.  x\fter  eight  days  of  extra-uterine  life  the  danger 
of  infection  is  passed. 

Symptoms. — The  symptoms  appear  in  from  a  few  hours  to 
three  (lays  after  birth,  rarely  later.  The  principal  indication 
of  the  disease  is  diarrhea.  The  liquid  feces  are  at  first  expelled 
with  considerable  straining  (tenesmus),  a  strong  stream  of 
yellow-colored,  fetid  discharge  being  shot  from  the  rectum. 
Later  the  evacuations  become  whiter  in  color  and  thinner  in 
consistency,  often  mixed  with  blood  and  food.  The  patient 
rapidly  grows  weak,  languid,  refuses  to  suck,  the  eyes  become 
retracted  and  dull,  the  anus  relaxes,  causing  fecal  incon- 
tinence, the  hair  coat  becomes  erect,  and  finally  under  symp- 
toms of  coma  death  occurs.  The  temperature  is  somewhat 
elevated  (105°  F.)  in  the  early  stages,  but  later  may  become 
subnormal.    There  is  also  dypsnea  and  rapid  pulse. 

Diagnosis. — l^sually  easy.  This  infcdiovs  dysentery  is  dif- 
ferentiated from  sporadic  diarrhea  of  young  animals  in  that  it 
affects  only  those  less  than  one  week  old,  induces  a  fetid, 
exhaustive,  and  rapidly  fatal  diarrhea  and  assumes  an 
enzootic  form.  In  acute  gastro-intestinal  catarrh  ("scours") 
due  to  dietetic  irregularities  older  sucklings  are  attacked,  the 
general  symptoms  are  much  less  pronounced,  and  the  feces 
are  thicker,  yellower,  and  less  fetid. 


DISEASES  OF  NEWBORN   ANIMALS  307 

Course.^ — The  course  is  usually  very  rapid,  leading  to  death 
ill  from  twelve  to  forty-eight  hours.  The  sooner  after  birth 
the  s;sTriptoms  appear  the  more  fatal  and  rapid  the  course. 
Occasional  cases  may  linger  as  long  as  a  week. 

Prognosis. — Bad.  ^Mortality  90  per  cent.  Recovery  follows 
a  protracted  convalescence  and  results  in  an  unthrifty  calf 
(chronic  pneumonic  lesions) . 

Treatment. — INIedicinal  treatment  is  usually  worse  than 
useless,  as  it  rarely  pre\'ents  death,  and  encourages  the  further 
spread  of  the  disease.  Ordinarily  it  pays  to  kill  the  infected 
suckling  and  render  its  carcass  harmless  by  cremation  or  deep 
burial.  When  an  outbreak  occurs  every  effort  should  be  made 
to  eradicate  the  infected  sources  by  a  thorough  disinfection  of 
the  barn,  hind  parts  and  genitals  of  the  dam,  before  and  after 
parturition,  and  the  navel  stump  of  the  newborn  animals,  if  it 
still  be  healthy.  All  fecal  discharges  should  be  removed  and 
sterilized  with  a  2  per  cent,  formaldehyd  solution.  The  stable 
partitions,  mangers,^  floors,  should  be  thoroughly  disinfected 
and,  if  possible,  given  a  coat  of  whitewash.  The  after-birth, 
dead  sucklings,  and  postpartum  vaginal  discharges  should  be 
completely  destroyed.  The  vagina  of  the  dam  should  be 
douched  with  a  warm  solution  of  2  per  cent,  carbolic  acid,  the 
external  genitals,  buttocks,  tail,  and  udder  being  also  washed 
with  the  antiseptic.  The  navel  of  the  newborn  animal  should 
not  be  ligated,  but  before  it  has  had  an  opportunity  to  become 
infected,  covered  with  some  astringent,  antiseptic  powder 
which  will  aid  its  desiccation.  The  meconium  is  best  removed 
by  the  colostral  milk  of  the  dam,  but  before  sucking  is  per- 
mitted the  udder  and  teats  should  be  disinfected  with  a  non- 
poisonous  antiseptic  (creolin) .  Hand-fed  sucklings  should  be 
allowed  the  colostral  milk  for  the  first  two  days.  To  prevent 
outbreaks  in  contaminated  premises  it  is  recommended  to 
remove  the  pregnant  dams  to  uninfected  places  at  least  six 
weeks  before  parturition.  As  the  infection  seems  to  be  re- 
tained in  the  genital  passages  for  some  time  a  shorter  period 
does  not  suffice.  Serum  therapy  has  been  tried  in  Europe. 
A  polyvalent  colon  serum  has  been  employed  with  some  degree 

^  If  the  floor  is  earth  it  should  be  removed  to  the  depth  of  at  least  one 
foot  and  then  filled  in  with  fresh  clay. 


308         ACUTE  GENERAL  INFECTIOUS  DISEASES 

of  success  (Jensen).  Experiments  to  produce  active  immunity 
of  the  fetus  in  utero  by  inoculating  subcutaneously  pregnant 
cows  with  sterile  extracts  of  colon  bacilli,  have  been  made 
with  as  yet  conflicting  results. 

Pyosepticemia  of  Sucklings  { Pastenrcllusis  Neo7iatorum). 
Pi/cinic  Art  III- If  is.  Joint  III.  Oiiiplidloplilcbitis.  Xavcl  III. 
— Definition. — This  is  an  acute  contagio-infectious  disease  of 
animals  less  than  one  month  old,  due  to  navel  infection,  and 
characterized  In*  joint  lesions  usually  of  a  i)urulent  character. 
It  is  accompanied  by  septicoi)yemia.  i*eracute  cases  take  the 
form  of  a  general  septicemia. 

Occurrence. — The  disease  is  wide-spread  and  occurs  in  prac- 
tically all  breeding  districts.  Foals  and  calves  are  most  com- 
monly ati'ected.  Like  the  dysentery  of  sucklings,  with  which 
it  is  closely  related,  it  often  appears  as  an  enzootic,  attacking 
large  numbers  of  young  animals,  and,  as  it  is  generally  fatal, 
seriously  interferes  with  breeding  operations. 

Etiology. — In  calves  the  Bacterium  bovisepticum  and  the 
colon  bacillus,  acting  jointly,  are  accused.  In  colts  various  pus 
cocci  (staphylococci  and  streptococci)  have  been  found  in  the 
organs,  blood  and  joints.  It  is  very  probal)le  that  several 
pathogenic  micnxirganisms  are  related  etiologically  to  the 
disease. 

Natural  Infection. — K.vtra-iitcrinc. — T'/a  navel  cord  which 
has  not  yet  become  dried  and  shriveled  and  still  contains  the 
^Yhartonian  gelatin.  The  danger  of  infection  is  probably 
greatly  enhanced  by  ligation  as  is  usually  practised  in  animals. 
Naturally,  filthy  bedding  or  floors  or  ground  covered  with 
manure,  urine  or  the  discharges  from  the  infected  navel  of  a 
developed  case  of  the  disease  increase  the  danger.  It  happens, 
therefore,  that  a  sporadic  case  can  s))read  the  infection  until 
every  colt  or  calf  born  on  the  premises  beconies  a  victim. 

Intra-uterine  Injection. — As  some  animals  are  born  with  the 
disease  (symptoms  at  birth;  pathological  lesions  present  too 
old  to  have  de\'(>lope(l  since  birth),  an  infection  in  utero  from 
the  pregnant  dam,  in  whose  blood  ])iitliogcnic  bacteria  have 
appeared,  is  assumed. 

A  further  possil^lity  would  be  the  ])crmanent  infection  of 
the  uterus  of  the  dam  and  the  passage  of  the  bacteria  from  it 


DISEASES  OF  NEWBORN  ANIMALS  309 

to  the  placenta  and  fetus.  This  would  explain  those  cases 
where  a  gi\'en  mare  bears  year  after  year  colts  which  are  born 
with  the  tlisease.  In  cases  of  antepartum  infection  the  navel 
is  usually  intact. 

Necropsy. — The  postmortem  lesions  vary,  depending  on 
whether  the  case  was  peracute,  acute,  or  chronic. 

(a)  Peracute.  There  are  no  marked  lesions  except  those 
of  a  general  septic  infection  such  as  cloudy  swelling  of  the 
parenchymatous  organs,  petechise  and  ecchymoses  in  the 
serous  and  mucous  membranes  and  acute  swelling  of  the 
lymph  glands. 

{b)  In  acute  cases  the  navel  is  usually  swollen  and  firm  and 
the  navel  ring  is  open.  Purulent  or  putrid  exudate  may  be 
pressed  out.  Quite  frequently  an  abscess  forms  in  the  ab- 
dominal wall.  The  umbilical  vein  and  one  or  both  umbilical 
arteries  are  distended  at  intervals  or  throughout  their  whole 
length.  On  palpation  they  feel  firm  or  fluctuating.  When 
opened  a  dirty  red,  often  fetid  exudate  flows  out.  The  inner 
surface  of  the  bloodvessels  may  be  covered  with  a  fibrinous 
coagulum  and  is  sometimes  ulcerous.  The  infection  may 
involve  the  peritoneum,  leading  to  an  adhesive  peritonitis, 
causing  adhesions  among  the  abdominal  organs.  The  portal 
vein  and  its  branches  show  thrombi  extending  into  the 
liver. 

Metastatic  abscesses,  especially  of  the  lungs,  liver  and 
lymph  glands,  are  not  infrequent.  Occasionally  there  may  be 
present  pleuritis  antl  pericarditis.  A  fibrinous  or  suppurative 
panophthalmia  is  not  rare.  The  affected  joints,  especially 
the  tarsal  and  carpal,  show  suppurative  artliritis.  The  peri- 
articular connective  tissue  is  infiltrated  with  either  a  sero- 
fibrinous or  seropurulent  exudate;  periarticular  abscesses  are 
not  uncommon.  A  communication  between  the  abscess  and 
the  diseased  joint  cavity  is  not  unusual.  The  adjacent  tendon 
sheaths  may  be  also  involved. 

(c)  Chronic  Cases. — The  changes  here  are  frequently  in  the 
lungs,  such  as  bronchopneumonia,  with  fibrinous  or  sero- 
fibrinous pleuritis,  and  pericarditis.  In  the  later  stages  case- 
ous foci  are  found  in  the  lungs.  The  mediastinal  and  peri- 
bronchial lymph  glands  are  often  enlarged  and  caseated.    The 


310         ACUTE  GENERAL   INFECTIOUS  DISEASES 

cadaver  is  emaciated  and  shows  symptoms  of  treiierai  anemia 
and  cachexia. 

Symptoms. — In  pyoseijticemia  of  sncklin^s  tlie  disease  may 
ai)i)ear  clinically  as  a  general  septicemia,  an  alfection  of  the 
joints  or  of  the  navel,  and  may  he  complicated  with  metastatic 
chaiifjes  in  internal  organs  (hmgs,  li\'er,  kidneys,  mesenteric 
glands,  brain,  etc.).  The  clinical  picture  will  therefore  vary. 
In  calves  the  disease  is  often  less  acute  than  in  colts  and  is  less 
ajjt  to  involve  the  articulations.  Both  local  and  general 
sNinptoms  are  observed,  the  local  often  being  noticed  first. 
Three  clinical  forms  of  the  disease  are  recognized : 

(a)  Septicemic  Form. — In  the  septicemic  form  there  appear 
within  a  day  or  two  after  birth  the  following  sAinptoms: 
refusal  to  suck;  the  patient  is  languid,  remains  recumbent, 
and  if  lifted  to  its  feet  is  rarely  able  to  stand,  the  head  held 
low,  the  whole  body  limpid.  The  temperature  is  elevated 
(105°  F.),  the  heart  beat  rapid  and  the  respirations  dyspneic. 
Death  occurs  in  one  or  two  days.  In  some  cases,  due  to 
metastasis,  symptoms  in  internal  organs  (lungs)  develop. 

(6)  Articular  Form. — Most  frequently  in  colts  the  first 
symptom  noted  is  swelling  of  a  joint  or  joints  appearing  within 
a  few  days  after  birth.  The  owner  generally  assumes  that  the 
swollen  part  has  been  tread  on  by  the  dam.  The  enlargement 
occurs  in  a  limb  joint  (tarsal,  carpal,  femorotibial)  and  is 
inflammatory  in  character.  The  surrounding  tissue  is  edema- 
tous. While  the  swelling  sometimes  ])romptly  disappears, 
generally  it  persists,  fluctuates  and  perforates  or  is  lanced,  dis- 
charging pus.  Flexion  of  the  aft'ected  joint  causes  pain  and 
severe  lameness.  If  many  joints  are  attacked  the  young 
patient  may  be  unable  to  stand.  Marked  suppuration  does 
not  always  take  ])lace.  The  swelling  may  ne\'er  open  spon- 
taneously, but  leads  to  a  subacute  or  chronic  arthritis  with 
periarthritis,  causing  temporary  or  permanent  enlargement  of 
the  joint. 

(f)  Umbilical  Form. — In  some  cases  a  local  inflanunation 
appears,  the  navel  becoming  hot,  painful,  and  swollen,  the 
stump  moist  and  discharging  pus  or  ichor.  Between  the 
umbilicus  and  the  ensiform  cartilage  a  firm  strand,  the  size 
of  a  finger,  may  be  felt  in  the  abdominal  wall  running  toward 


DISEASES  OF  NEWBORN  ANIMALS  311 

the  liver.  The  k)cal  symptoms  may  abate  in  a  few  days  and 
the  patient  recover,  or,  on  the  other  hand,  a  general  septic 
infection  ending  in  death  resnlts.  Not  infrequently  metas- 
tatic abscesses  form  in  parenchymatous  organs  producing 
symptoms  varying  with  their  distribution: 

(a)  Lungs. — If  the  lungs  are  involved  the  young  patient 
will  cough,  have  nasal  discharge  and  show  dyspnea.  On 
auscultation  bronchial  sounds,  rales,  and  rhonchi  may  be 
heard  and  on  percussion  areas  of  dulness  and  tympany.  The 
animal  becomes  anemic,  emaciated,  and  extremely  weak,  re- 
maining most  of  the  time  lying  on  the  sternum.  In  this  form 
it  may  linger  several  weeks. 

(6)  Stomach  and  Bowels. — The  principal  s^onptoms  are 
loss  of  appetite,  abdominal  pain,  and  diarrhea.  The  feces 
are  like  those  described  under  Dysentery  of  Newborn 
Animals. 

(c)  Sjnnal  Cord. — When  the  cord  is  invaded  by  metastatic 
abscesses,  symptoms  of  paraplegia  appear.  These  may  come 
on  suddenly  or  gradually  and  follow  a  period  of  apparent 
recovery.  In  some  cases  of  spinal  paralysis  the  preceding 
navel  symptoms  may  have  been  entirely  overlooked. 

(d)  Brain. — The  patient  is  usually  very  dull  and  uncon- 
scious of  its  surroundings.  It  may  show  forced  movements, 
spasms  and  convulsions,  opisthotonos,  wry-neck,  and  par- 
alysis. 

Diagnosis. — Generally  not  difficult.  When  diarrhea  is 
present  a  differentiation  between  joint  ill  and  dysentery  is 
impossible.  If  the  navel  is  intact  and  joint  swellings  are 
absent,  the  diagnosis  could  be  made  only  by  a  knowledge 
that  the  disease  exists  on  the  premises  (other  sucklings  show- 
ing a  more  characteristic  form  of  the  disease). 

Course. — Peracute  cases  die  in  twelve  to  forty-eight  hours. 
In  the  acute,  septicemic  form  the  patients  die  in  two  or  three 
days.  In  subacute  cases,  especially  when  the  infection  occurred 
late  after  birth,  the  navel  infection  remains  local  and  eventu- 
ally heals,  the  patient  under  proper  treatment  recovering  in 
two  or  tliree  weeks.  Chronic  (lung)  cases  may  last  one  or 
two  months.  If  the  abscesses  in  the  lungs  or  liver  become 
fully  encapsuled,  recovery  may  even  take  place. 


312         ACUTE  GENERAL  INFECTIOUS  DISEASES 

Prognosis.  Bad.  Depending'  on  the  iv^v  attacked  and  tlie 
form  the  disease  assumes,  the  mortality  will  vary  greatly.  It 
is  higher  in  colts  than  in  calves,  relativel\-  more  resistant  to 
pus  infections.  Fully  (iO  to  90  per  cent.  die.  Most  sucklings 
which  do  reco\er  remain  stunted  and  do  not  "do  well"  for 
months  after  the  attack  (internal  abscesses).  In  cases  of 
joint  afi'ection  in  colts,  if  the  supi)uration  is  mild,  recovery  is 
common.  When  general  symptoms  api)ear  the  prognosis  is 
bad.  Bowel  symptoms  (diarrhea)  generally  promptly  lead  to 
death. 

Treatment. — An  internal  treatment  is  useless.  When  gen- 
eral septicemia  is  present  the  patient  is  beyond  aid.  The  most 
rational  treatment  is  surgical  and  applied  to  the  primary  seat 
of  infection — the  umbilicus.  It  should  be  thoroughly  disin- 
fected (tincture  of  iodin),  abscesses  opened,  necrotic  portions 
carefully  removed,  and  drainage  jM-ovided.  At  the  same  time 
the  patient  should  be  kept  in  a  light,  \\ell-ventilated,  clean 
place.  Painting  the  joint  swellings  with  iodin  tincture  is 
recommended.  ()])ening  them  to  evacuate  pus,  while  rarely 
of  therapeutic  value,  is  demanded.  If  there  is  no  evidence  of 
pus  (heat,  pain,  firm  fluctuation,  temperature),  the  knife 
should  be  spared. 

^'accination.  The  use  of  polyvalent  or  autogenic  bacterins 
to  arrest  the  progress  of  the  disease  is  highly  reconnnended  by 
practitioners.  In  some  cases  the  results  seem  very  satis- 
factory.   More  ex]ieriments  are  desired. 

Prevention. — Where  infection  threatens,  the  dam  about  to 
be  deli\ercd  should  be  placed  in  a  clean,  light,  well-ventilated 
stall  (preferably  a  maternity  stall  with  .cement  Hoor  and 
walls)  and  the  bedding  si)rinkled  with  some  non-poisonous 
antiseptic  (creolin).  The  genitals  may  be  flushed  out  with 
some  good  antiseptic  (creolin  2  per  cent.)  and  the  tail  and 
buttocks  cleaned  with  it.  As  soon  as  the  young  animal  is 
born  the  navel  cord  should  be  gently  "niilked"  with  dis- 
infected hands,  to  remove  the  Whartonian  gelatin,  and  thor- 
oughly covered  with  a  gocxl  antiseptic  strew  powder  (dried 
alum,  cami)hor,  starch,  ecpial  i)arts)  to  aid  in  the  desiccation 
of  the  cord.  The  application  of  the  strew  powder  should  l)c 
rc])eated  often  until  the  stump  is  completely  shriveled  and 


INFLUENZA  OF  THE  HORSE  313 

dried.  By  frequent  application,  say  once  every  half-hour  for 
the  first  two  hours  after  birth,  the  cord  becomes  thoroughly 
mummified  in  two  to  four  hours  (Williams). 

INFLUENZA  OF  THE  HORSE. 

Under  the  collective  term  "influenza"  intermittently  have 
been  grouped  together  at  least  two  acute,  infectious  diseases 
one  of  which  assumed  the  form  of  a  general  infection  of  the 
blood  with  inflammation  of  the  mucous  membranes,  subcutis, 
tendon  sheaths  and  tendons,  and  the  other  an  infectious 
lobar  pneumonia  or  pleuropneumonia.  From  a  purely  clinical 
standpoint  some  authorities  (DieckerhofF,  Bang)  have  pro- 
nounced influenza  not  to  be  a  clinical  entity.  They  assumed 
that  under  this  head  at  least  two  separate  and  distinct  dis- 
eases existed  which  dift'ered  in  their  pathogenesis,  period  of 
incubation  and  symptomatology.  They  were  therefore  given 
separate  names.  In  Germany  the  catarrhal  form  was  known 
as  "Staupe"  (influenza)  and  the  pectoral  as  "Brustseuche" 
("chest  plague").  Dieckerhoft'  described  a  third  disease,  in- 
cluded under  the  term  influenza,  which  he  called  "Skalma." 

The  recent  experiments  of  Gaft'ky  and  Liilii-s  which  con- 
cerned the  etiological  factor  primarily  indicate  that  the  term 
"influenza"  has  been  made  too  inclusive.  Their  results  seem 
to  substantiate  the  work  done  by  former  authorities,  espe- 
cially Dieckerhoft'  and  Bang.  In  the  light  of  our  present 
knowledge  it  seems  advisable  to  classify  under  the  term 
influenza  two  separate  and  distinct  diseases:  (a)  Influenza. 
{h)  Infectious  fibrinous  pneumonia  of  the  horse. 

Influenza  of  the  Horse  {Catarrhal  Fever,  Pink  Eye,  Typhoid 
Fever). — Definition. — Influenza  is  an  acute  contagio-infectious, 
usually  enzootic,  disease  of  the  horse  which  is  characterized  by 
inflammation  of  the  mucous  membranes,  subcutis,  and  ten- 
dons.   It  is  due  to  a  filterable  virus. 

Occurrence. — The  disease  is  very  wide-spread,  occurring  in 
all  countries.  North  America  was  visited  by  an  epizootic  of 
influenza  in  1776  and  again  in  a  still  severer  form  in  1870-72 
when  it  swept  the  continent  from  Canada  to  the  Ohio,  and 
westward  to  California.    The  disease  is  now  permanent  in  this 


314         ACUTE  GENERAL  INFECTIOUS  DISEASES' 

country  where  it  is  kept  ali\'e  by  the  unsanitary  sta])les  of 
horse-dealers  and  in  livery  barns  from  whence  it  is  from  time 
to  time  spread.    It  may  also  attack  asses,  mules  and  zebras. 

Etiology, — The  most  recent  investigations  indicate  that  the 
cause  of  influenza  is  a  filterable  virus  which  appears  in  the 
blood  and  i)rol)ably  other  body  fluids,  (iaffky  produced  in- 
fluenza in  healthy  horses  by  subcutaneous  injections  (5  c.c.) 
of  defibrinated  blood  from  naturally'  infected  horses.  The 
period  of  incubation  is  from  hvv  to  six  days.  When  the  blood 
was  injected  intravenously  the  ])eriod  of  incubation  was  only 
four  days.  In  artificially  infected  horses  the  characteristic 
symptoms  were  produced  in  forty  hours.  Similar  experiments 
made  with  filtered  blood  serum  gave  positive  results.  The 
infectiousness  of  the  blood  was  annihilated  by  the  addition  of 
the  citrate  of  ammonia.  In  no  case  was  he  able  to  obtain 
growths  on  culture  media  from  either  the  blood  or  blood 
serum  used. 

Natural  Infection.^The  disease  is  probably  sjjread  b\'  the 
nasal  discharge  and  feces  of  infected  horses.  In  all  probability 
apparently  recovered  cases  may  be  "germ  carriers"  introduc- 
ing the  disease  into  stables  and  when  brought  in  contact  with 
susceptible  individuals.  Indirectly  the  infection  may  be 
carried  by  contaminated  food,  bedding,  manure,  stable  uten- 
sils, harness  or  in  the  clothing  of  grooms,  horsemen  and 
veterinarians.  Many  sale  and  livery  stables,  due  to  their 
lack  of  light,  ventilation  and  cleanliness,  may  harbor  the 
infection  for  an  indefinite  period  ("stable  miasma")  and  all 
horses,  esi^ecially  "green"  horses  from  the  country,  ]jlaced  in 
them  fall  victims  of  the  disease.  The  same  is  true  of  railway 
cars  and  stockyards  which  have  not  been  properly  disin- 
fected. Public  watering  troughs  may  also  harbor  infection 
and  thus  contribute  to  the  spread  of  the  disease.  Although 
influenza  is  commonly  enzootic  it  not  unrarely  assumes  an 
epizootic  form.  While  it  appears  at  all  seasons  of  the  year, 
in  the  late  winter  and  early  si)ring  horses  seem  most  predis- 
posed. This  is  i)r()ba])ly  due  to  the  condition  of  the  mucous 
membranes,  which  are  generally  catarrhally  inflamed  from 
"colds"  in  these  seasons.  Influenza  will  attack  horses  of  all 
ages,  but  it  is  not  so  common  in  colts  less  than  a  year  old,  nor 


INFLUENZA  OF  THE  HORSE  315 

aged  horses.  Horses  three  to  five  years  of  age  are  most  fre- 
ciiieiitly  affected.  One  attack  produces  lasting  hnmunity. 
Horses  which  have  had  influenza  may,  however,  take  in- 
fectious pneumonia,  and  vice  verm.  The  infection  is  most 
commonly  taken  in  with  the  food  and  water.  Infection  via 
respiratory  tract  is  highly  probable  but  not  proven. 

Symptoms.— The  period  of  incubation  is  usually  less  than  a 
week.  A  minimum  period  of  one  day  and  a  maximum  of  ten 
days  is  recognized.  The  initial  symptoms  in  many  cases  are 
moderately  developed,  but  in  the  majority  they  are  quite 
intense.  Usually  the  first  symptoms  noticed  by  the  owner  or 
caretaker  are  loss  of  appetite,  dulness,  and  marked  languor. 
The  patient  stands  with  head  down,  eyes  closed,  ears  drooped, 
appearing  excessively  fatigued.  The  gait  is  staggering,  and 
crackling  of  joints  is  heard  when  the  patient  is  moved. 

The  temperature  is  elevated  (103°  to  105°  F.).  It  usually 
drops  by  crisis  on  the  second  or  third  day.  The  pulse  in  the 
earlier  stages  is  relatively  low  compared  with  the  fever,  but  as 
soon  as  cloudy  swelling  of  the  heart  begins  it  goes  up  to  60  to 
100,  and  becomes  irregular  and  weak. 

Eye  Lesions. ^ConjunctiYitis  appears  early,  and  later  kera- 
titis and  iritis  (exudate  in  anterior  chamber,  contraction  of 
pupil,  etc.).  The  blood  is  charged  with  bile  pigment,  hence 
the  conjunctiva  assumes  a  yellowish,  ochre,  or  a  natural 
mahogany  color.  Sometimes  a  phlegmonous  conjunctivitis 
with  marked  swelling  and  e version  of  the  eyelids  occurs. 
These  symptoms  generally  rapidly  subside,  provided  the 
cases  take  the  normal  benign  course. 

Respiratory  Tract— Cough  is  usually  present.  It  is  gen- 
erally strong  and  moist.  Nasal  discharge,  at  first  clear  but 
later  turbid  and  more  profuse,  is  a  constant  symptom.  The 
submaxillary  glands  are  swollen.  The  patient  shows  moder- 
ate dyspnea;  the.  respirations  20  to  25.  Percussion  normal. 
Auscultation    exaggerated,    vesicular   breathing   and   moist 

rales. 

Digestive  Tract.— Lost  or  impaired  appetite;  durmg  the 
fever  increased  thirst  is  noted.  Usually  symptoms  of  catarrhal 
stomatitis  and  pharyngitis  are  present  (coated  tongue,  warm, 
congested  mucous  membranes;  regurgitation  of  water  through 


316         ACUTE  GENERAL  IXFECriOl'S  DISEASES 

the  nostrils).  The  fiunis  arc  swollen  ("lanii)as"),  and  alon<,f 
their  border  a  marked  yellowish  discoloration  is  seen.  The 
bowels  dnring  the  febrile  stajjc  are  constipated,  the  feces 
passed  in  the  form  of  hard,  small,  mncons-c()\ered  pellets  of 
sour  odor.  Later  they  become  soft  and  a  fetid,  exhaustive 
diarrhea  with  tenesmus  sets  in.  In  some  cases  moderate  colic 
symptoms  occur  (pawing,  lying  down,  slight  distention  of 
abdomen). 

irin(>(/euital  Tract. — During  the  height  of  the  fever  very 
little  urine  is  voided.  Its  specific  gravity  is  high,  color  dark, 
reaction  acid.  It  is  rich  in  sediment,  lender  the  microscope 
tube  casts  and  epithelial  cells  (renal  ])elvis,  bladder)  are  found 
in  it.  With  the  falling  of  the  temperature  a  critical  polyuria 
develops.  In  mares  the  vulva  may  swell  and  a  mucopurulei.it 
discharge  be  present.  Pregnant  mares  often  abort.  In 
stallions  the  scrotum  is  often  enlarged  and  orchitis  may  be  a 
symptom. 

Slchi. — While  there  is  generally  an  edema  of  the  hind  limbs 
present  in  influenza,  in  some  outbreaks  it  is  much  more  pro- 
nounced than  in  others.  With  increased  heart  weakness, 
edemas  appear  in  pendent  portions  of  the  body  (under  chest, 
abdomen,  udder  or  scrotum).  Occasional  cases  of  tendo- 
vaginitis, particularly  of  the  flexor  tendons,  are  noted,  and 
once  in  a  while  laminitis  occurs.  The  patients  usually  lose 
flesh  rapidly,  and  become  very  weak  and  debilitated. 

A  very  dangerous  conij)lication  is  ])neumonia  or  pleuro- 
pneumonia, which  usually  assumes  the  catarrhal  form,  and 
may  be  hemorrhagic  in  character.  Such  cases  seriously  dis- 
turb the  functions  of  the  heart,  and  kidneys  and  often  lead  to 
(leath. 

Diagnosis. — The  diagnosis  is  usually  not  difficult.  The 
rapid  spread  of  the  disease  from  animal  to  animal,  the  icteric 
mucous  membranes,  conjunctivitis  and  skin,  edemas  differen- 
tiate it  from  other  diseases  attended  by  high  fe\'er.  When 
these  s,vmpt()ms  are  absent  the  highl.\'  infectious  character  of 
the  disease,  as  e\idence(l  In'  the  ra])id  s])rea(l,  is  significant. 

While  a  differentiation  between  infiuenza  and  infectious 
pneumonia  of  the  horse  can  usually  be  made  if  the  course  of 
the  disease  can  be  studied,  at  first  visit  it  mav  be  ver\'  diffi- 


INFLUENZA  OF  THE  HORSE  317 

cult.  The  prodromal  symptoms  of  the  two  diseases  are  ^'ery 
similar.  The  high  initial  fever,  the  swelling  and  icteric  dis- 
coloration of  the  conjunctiva,  the  contagiousness  and  the 
inflammatory  swellings  in  the  subcutis  and  tendon  sheaths 
are  common  to  both.  Usually,  however,  on  the  second  or 
third  day  in  infectious  pneumonia,  tangible  symptoms  of 
pneumonia  develop;  in  influenza  pneumonia  occurs  as  a 
complication,  and  usually  much  later  in  the  course  of  the 
disease.  Fiu'thermore,  influenza  is  more  apt  to  atta,ck  the 
intestinal  tract  early.  A  differentiation  between  influenza 
and  infectious  anemia  would  become  important  only  in  dis- 
tricts in  which  the  latter  disease  exists.  In  infectious  anemia 
no  catarrhal  symptoms  develop,  the  mucous  membranes  show 
petechife,  the  blood  serum  is  opalescent  and  plainly  tinged 
with  red.  Infectious  anemia  is  not  highly  infectious.  From 
strangles  influenza  is  distinguished  by  the  tendency  for  lymph 
glands  to  suppurate,  which  characterizes  the  former  disease. 

Course. — The  course  is  usually  about  one  week  or  the  disease 
may  terminate  favorably  in  less  time,  provided  no  complica- 
tions arise.  When  the  disease  progress  is  interrupted  by 
pneumonia,  encephalitis,  enteritis,  or  degeneration  of  the 
heart  muscle  the  course  is  protracted  and  the  termination 
fatal.  As  a  rule,  however,  influenza  is  a  mild  disease,  and 
unless  the  patient  is  worked,  kept  in  unsanitary  surroundings, 
or  given  too  much  medicinal  treatment,  recovery  in  a  few 
days  is  the  rule. 

Prognosis. — The  mortality  is  1  to  4  per  cent.  During  some 
outbreaks  the  disease  appears  more  malignant  than  in  others, 
and  complications  are  commoner.  The  continuation  of  a 
rather  high  fever  for  not  longer  than  five  or  six  days  is  2J<?''  se 
of  no  significance  provided  the  pulse  remains  good,  the  patient 
does  not  become  dyspneic,  and  no  diarrhea  attend. 

Treatment. — Most  important  in  the  treatment  of  a  self- 
limiting  disease  like  influenza  is  to  provide  the  patient  with 
light,  ventilation,  and  cleanliness.  In  mild  sunny  weather,  if 
at  all  feasible,  place  the  patient  out  of  doors  during  the  day. 
The  food  should  be  nourishing  and  easily  digested,  and  given 
in  small  rations  (grass,  alfalfa,  a  bran  mash  with  plenty  of 
salt,  scalded  oats,  etc.).    To  induce  the  patient  to  eat,  some 


318         ACUTE  GENERAL  INFECTIOUS  DISEASES 

brown  sugar  may  be  strewn  ()\"er  the  feed.  In  case  a  meal  is 
refused  or  not  entirely  eaten  it  should  not  remain  indefinitely 
in  the  feed  box,  but  be  removed  and  the  box  cleaned.  Skim 
milk  may  he  gi\en  (three  or  four  gallons  daily)  if  the  patient 
will  drink  it.  Hanging  blankets  wet  with  cold  formalin  solu- 
tion in  the  stable  helps  lower  the  temperature  in  hot  weather 
and  assists  disinfection.  A  thorough  cleaning  up  and  dis- 
infection of  the  infected  quarters  will  do  more  to  reduce  the 
mortaUty  than  drugs.  The  unequal  distribution  of  the  surface 
temperature  should,  be  regulated  by  proper  grooming.  The 
legs  should  be  covered  with  Derby  or  flannel  bandages,  which 
tend  to  prevent  edema.  Medicinal  treatment  should  only 
be  employed  when  absolutely'  necessary.  ()\'er(lrugging  in 
influenza  always  increases  the  mortality'.  The  following 
conditions  may  require  medicinal  aid : 

Fever. — The  fever  should  be  let  alone  unless  it  reaches  an 
unusual  height  or  is  continuing  rather  indefinitely  and  seri- 
ously alYecting  the  heart  action.  It  ma>'  be  reduced  by  cold 
rectal  infusions  which  not  only  lower  temperature  but  stimu- 
late peristalsis  and  unload  the  bowels.  The  use  of  antipy- 
retics, such  as  acetanilid  or  phenacetin  (Sij  every  three  hours) 
is  dangerous,  as  both  drugs  are  ])owerful  heart  (lei)ressants. 
They  should  be  administered,  if  at  all,  with  caution.  Sodium 
salicylate  (oiv)  is  less  dangerous  in  this  regard,  but  may 
irritate  the  stomach. 

Heart  Wenlmess. — When  the  pulse  becomes  ra])id  and  weak 
one  dose  of  digitalis  (Squibb's  fluidextract  oij-iv)  has  a 
remarkable  toning  effect.  Strophanthus  (5ij-iv),  caffein 
(5ss-j),  camphor  oil  (subcutaneously  S^^-j)  ^re  also  effec- 
tive. When  the  pulse  is  strong  enough,  alcohol  (brandy 
(Siij)  with  ether  (§ss)  in  a  pint  of  cold  water)  is  of  service. 

GaMro-'mU'stinal  Trad. — Artificial  Carlsbad  salts  (5ij-iij) 
to  which  bitter  agents  (gentian,  nux  vomica)  are  added  are 
useful.  Dram  doses  of  a  solution  of  strychnin  nitrate  in  water 
(strychnin  gr.  j,  water  oj)  uiiiy  he  used,  liowel  disinfectants 
are  also  employed,  as  (•re()lin  (5ss-5j)  or  naphtliolin  (5ss). 
Diarrhea  may  be  fought  with  astringents  like  tannin  with 
opium.  Starch  clysters  are  helpful.  The  i)rofuse  diarrhea 
attending  septicemia  is  impossible  to  check.     Calomel   (gr. 


INFLUENZA  OF  THE  HORSE  319 

xv)  with  bicarbonate  of  soda  (giss)  mixed  with  powdered 
Hcorice  root  (§j),  smeared  over  the  teeth  as  an  electuary, 
may  be  tried. 

Skin.^Leg  sweUings  are  best  reduced  by  elastic  bandages, 
and  if  the  pulse  will  permit,  moderate  exercise.  Burrow's 
solution  to  which  a  little  gum  camphor  is  added  may  be  used 
as  a  leg  wash  under  the  bandage. 

Eyes.— The  eyes  should  be  treated  as  in  conjunctivitis 
(boric  acid  solution  2  per  cent.)  and  the  pulmonary  and 
pleural  symptoms  met  as  recommended  under  the  Diseases 
of  the  Respiratory  Tract. 

Convalescent  patients  should  not  be  worked  until  strong 
enough  and  full  appetite  returned.  The  animal  is  generally 
fully  recovered  fourteen  days  after  the  temperature  has 
become  normal. 

Infectious  Fibrinous  Pneumonia  of  the  Horse  {Chest 
Plague.  Pectoral  Influenza.  Plevrisij.  Slnjyping  Fever).— 
Definition. — An  acute,  febrile,  contagio-infectious  disease  of 
the  horse  which  in  typical  cases  appears  as  a  fibrinous  pneu- 
monia or  pleuropneumonia  with  which  is  associated  inflam- 
mation of  the  subcutis  and  tendon  sheaths.  In  mild  cases  it 
may  assume  the  form  of  a  general  febrile  disease  of  short 
duration. 

Occurrence. — Infectious  fibrinous  pneumonia  is  wide- 
spread, occurring  in  all  countries.  Statistically  it  is  difficult 
to  state,  however,  anything  definite  in  regard  to  its  prevalency, 
as  it  has  been  so  often  confused  with  influenza.  The  disease 
is  most  apt  to  appear  in  large  stables  in  which  many  horses 
are  kept,  and  especially  during  inclement  weather.  The  dis- 
ease in  passing  through  a  stable  does  not  usually  affect  the 
horses  in  the  order  in  which  they  stand  in  the  stalls,  the  in- 
fection tending  to  spread  unevenly,  skipping  apparently 
susceptible  horses.  Infectious  pneumonia  does  not  become 
epizootic  as  readily  as  does  influenza;  it  is  more  apt  to 
remain  confined  to  an  infected  stable,  from  which  it  may  be 
spread,  however,  by  a  convalescent  horse.  While  infectious 
pneumonia  will  not  involve  in  a  given  country  as  m.an>'  horses 
as  influenza,  on  account  of  its  higher  mortality  and  a  greater 
tendency  to  leave  behind  sequelse  ("heaves,"  relapsed  cases) 


320         ACUTE  GENERAL  INFECTIOUS  DISEASES 

which  may  permanently  impair  the  efficiency  of  tlie  horses 
attacked,  it  can  assume  even  greater  economic  importance. 

Etiology. — The  cause  of  infectious  pneumonia  of  the  horse 
has  not  yet  been  identified.  AcconUng  to  (nif^'ky  and  Liihrs 
the  bronchial  slime  of  an  infected  patient  contains  the  virus 
of  the  disease,  at  least  in  the  early  stages.  In  typical  cases  of 
infectious  i)neumonia  in  which  the  patients  were  destroyed  on 
the  third  or  fourth  day,  in  the  bronchi  was  found  a  (juantity 
of  yellow,  transparent,  viscid  fluid  which  contained  no  bac- 
teria. In  two  experiments  on  twenty-four  colts  inoculated 
with  this  fluid,  by  painting  it  upon  the  mucosa  of  the  nostrils 
and  in  the  mouth,  the  colts  became  tyi)ically  ill  with  infectious 
pneumonia  in  twent\'-three  to  forty-two  days.  Undoubtedly 
a  specific  virus,  which  may  be  filterable,  forms  the  true  cause 
of  the  disease.  In  all  probability,  however,  other  bacteria, 
principally  the  Streptococcus  pyogenes  equi,  and  the  Bacillus 
equi  septicus,  are  secondary  invaders,  contributing  to  the 
underlying  (lis('as(>  process  and  clinical  ])henomena. 

Natural  Infection. — The  way  in  which  the  disease  spreads 
naturally  is  at  present  not  known.  The  infection  seems  to  be 
spread  by  more  or  less  intimate  contact  between  the  sick 
horse  and  susceptible  ones.  The  transmission  through  inter- 
mediate agents,  such  as  food,  water,  stable  utensils,  etc.,  or 
thi'ough  persons  or  insects,  has  not  been  demonstrated  experi- 
mentally. However,  practical  experience  in  other  diseases 
and  with  this  disease  would  not  exclude  indirect  transmission. 
Sporadic  outbreaks  in  stables  could  be  explained,  however,  as 
coming  from  apparently  healthy  "germ  carriers"  or  "missed 
cases"  of  infectious  pneumonia,  /.  c,  where  still  exist  in  the 
lungs  or  occasionally  in  other  organs  unhealed  foci  of  infection. 
As  predisposing  factors  anything  which  reduces  the  resistance 
of  the  susceptible  animal  unquestionably  has  a  bearing  on  the 
origin  of  the  disease.  Therefore  refrigeration,  overwork,  bad 
sanitary  conditions,  become  predisposing  factors.  The  dis- 
ease is  rare  in  very  young  or  aged  horses,  and  occurs  usually 
in  animals  in  the  jn-ime  of  life. 

One  attack  produces  immimity  for  only  a  short  period. 
Individual  instances  are  recorded  in  which  a  given  horse  has 
suffered  repeated  mild  attacks  of  the  disease.     An  attack 


INFLUENZA  OF  THE  HORSE  321 

of  infectious  pneumonia  in  no  way  influences  the  susceptibility 
to  influenza  infection. 

Necropsy. — On  postmortem,  where  the  disease  has  assumed 
a  typical  form,  the  lesions  are  those  identified  with  fibrinous 
or  even  hemorrhagic  pneumonia,  with  a  marked  tendency  to 
gangrene.  The  extent  and  distribution  of  the  inflammation 
varies.  In  some  cases  the  pneumonia  is  of  the  lobar,  in  others 
the  lobular  t^-pe.  The  exudate  is  usually  of  a  hemorrhagic 
character.  Yellowish-gray  areas  of  necrosis  throughout  the 
lung  tissues  are  commonly  noted,  appearing  as  encapsuled 
pus  centres  or  gangrenous  foci. 

The  pleuritis  is  serofibrinous;  the  thorax  may  contain 
several  gallons  of  serous  exudate.  Adhesions  between  the 
lung  and  chest  wall  (adhesive  pleuritis)  is  a  common  finding. 
E^mpyema  of  the  thorax  may  be  present. 

In  the  gastro-intestinal  tract  appear  evidence  of  catarrh 
and,  especially  in  the  small  intestine  and  cecum,  inflamma- 
tory thickenings  and  ulcerations. 

Symptoms. — Infectious  pneumonia  of  the  horse  is  charac- 
terized by  pneumonia  and  pleuritis.  The  pneumonia  may 
assume  either  the  lobar  (benign)  or  lobular  (malignant)  type. 
(For  details  refer  to  the  chapter  on  Pneumonias  of  the  Horse.) 

Complications. — The  most  dangerous  complications  are: 
(a)  Parenchymatous  degeneration  of  the  heart  characterized 
by  tumultuous  heart  beat  and  a  rapid,  arrh\'tlmiic,  weak 
pulse.  (6)  Nephritis  distinguished  by  scantiness  of  urine 
(anuria)  and  albuminuria,  (c)  Septicemia,  usually  following 
pulmonary  gangrene,  and  recognized  by  continued  high  fever, 
chills,  rapid,  irregular  and  weak  pulse,  and  exhaustive  diar- 
rhea, (d)  Paraplegia  is  rarely  noted,  but  is  usually  a  fatal 
complication,  (e)  Paralysis  of  peripheral  nerves  (facial,  re- 
current) which  may  persist  for  several  weeks.  (/)  Swellings 
of  the  limbs  and  pendent  parts  of  the  body,  seen  especially 
in  the  latter  stages,  are  troublesome,  (g)  Tendinitis  and 
tendovaginitis,    (h)  Founder,    (i)  Abortion,    (j)  Decubitus. 

Diagnosis. — Usually  not  difficult.     Infectious  pneumonia 

cannot  be  differentiated  from  sporadic  lobar  pneumonias  if 

such  occur  in  the  horse.     Every  case  of  lobar  pneumonia, 

therefore,  should  be  isolated.    Obviously  this  does  not  apply 

21 


322         ACUTE  GENERAL  INFECTIOUS  DISEASES 

to  all  lobular  pneumonias,  especially  foreign  body,  nu'diciiuil, 
or  hyj)ostatic. 

Course. — When  the  pneumonia  assumes  the  lobar  type  with 
mild  i)leuritis  the  course  is  about  two  weeks.  If,  however, 
the  lobular  form  of  pneumonia  with  i)ronounced  bilateral 
pleuritis  is  present  the  course  is  prolonged  for  weeks,  with 
remissions  and  exacerbations,  either  ending  finally  in  death 
or  leaving  the  patient  permanently  wind-broken  (jileural 
adhesions;  roaring).    (See  Lobular  Pneumonia.) 

Prognosis. — The  mortality  is  1  to  4  per  cent.  The  following 
factors  are  important  in  the  prognosis;  they  are  all  grave 
symptoms:  (a)  Heart  paralysis  (rapid,  empty  pulse,  venous 
pulse) ;  (b)  extent  of  pneumonia  and  pleuritis  (bilateral  with 
great  effusion);  (c)  pneumonia  centralis  (sudden  dyspnea 
with  rise  in  the  temperatm-e  during  the  coiu'se  of  the  disease) ; 
(d)  hemorrhages  (epistaxis,  bloody  pleural  exudate) ;  (e)  tem- 
perature continues  high  for  over  a  week  or  is  remittent  in 
character;  (/)  diarrhea;  (g)  lung  gangrene;  (/?)  brain  symp- 
toms. 

Treatment. — See  Pneumonias  of  the  Horse. 

PURPURA    HEMORRHAGICA.   PETECHIAL   FEVER. 

Definition. — Purpura  hemorrhagica  is  an  acute,  non- 
contagious disease  the  result  of  a  toxemia  usually  developing 
as  a  sequela  to  a  specific  infectious  disease.  It  is  characterized 
by  marked  edematous  swellings  of  the  head  and  limbs  and 
petechiie  in  the  mucous  membranes  and  internal  organs. 

Occurrence. — Frequent  in  the  horse.  Cases  are  said  to 
occur  in  the  ox  and  the  dog.  The  disease  usually  is  seen  to 
follow  in  the  wake  of  an  outbreak  of  influenza  or  strangles, 
individual  cases  during  convalescence  developing  the  symp- 
toms which  tyjMfy  the  condition.  It  may  also  be  a  sequela  to 
other  debilitating  diseases,  especially  if  the  patient  has  been 
kept  in  unsanitary  surroundings  and  i)oorly  nourished.  It  is 
rare  in  horses  under  two  years  old,  but  may  attack  aged 
individuals. 

Etiology.— ^Purpura  in  horses,  as  noted,  is  a  secondary  dis- 
ease, and  is  j^robably  always  associated  with  a  hidden  pus 


PURPURA  HEMORRHAGICA— PETECHIAL  FEVER     323 

pocket  or  an  area  of  necrosis  somewhere  on  or  in  the  body  of 
the  animal  attacked.  It  is  therefore  most  apt  to  follow  dis- 
eases or  conditions  attended  by  pus  formation  or  necrosis 
(strangles,  pharyngitis,  empyema  of  facial  sinuses,  suppura- 
tive tooth  diseases,  internal  abscesses,  old  castration  wounds, 
necrosis  of  the  skin).  The  disease  is  not  transmissible  either 
by  inoculation  or  blood  transfusion;  there  are  no  specific 
organisms  found  in  the  blood.  Very  probable,  therefore,  is 
the  theory  that  toxins  originating  in  a  primary  pus  or  necrotic 
focus,  absorbed  by  the  blood,  in  time  intoxicate  the  animal, 
the  resistance  of  which  has  been  lowered  by  disease,  unh>-- 
gienic  en^irolmlent  and  poor  food.  ^Yhile  the  blood  itself 
seems  to  suffer  little  change  in  physical  properties,  the 
walls  of  the  bloodvessels,  especially  the  capillaries,  become 
porous  or  rupture,  allowing  the  blood  to  escape  into  the  sm- 
rounding  tissue.  Thus  smaller  petechia  or  more  extensive 
ecchymoses  are  produced.  From  the  larger  veins  the  transu- 
dation of  serum  leads  to  the  characteristic  swellings. 

Symptoms. — Petechise  in  the  mucous  membranes  of  the 
head.  The  hemorrhagic  spots  vary  in  size  from  a  hemp  seed 
to  a  bean.  Sometimes  on  the  nasal  mucosa  (septum  and 
turbinates)  the  areas  assume  the  form  of  stripes  or  striations, 
the  membrane  being  swollen.  The  petechia^  have  a  purple 
color.  Sometimes  ulceration  is  noted.  There  is  nasal  dis- 
charge of  a  yellowish  or  reddish  serum  or  fluid  blood.  In 
the  eyelid  conjunctivitis  is  present  with  petechise  and  slight 
sanguineous  discharge.  The  mucous  membranes  of  the 
mouth,  though  more  rarely,  may  also  be  involved. 

Swellings  of  the  skin  usually  appear  with  the  petechia  or 
follow  in  a  day  or  two.  These  are  often  at  first  isolated,  flat- 
tened, urticaria-like  tumefactions  from  the  size  of  a  pigeon's 
egg  to  that  of  a  grapefruit,  and  larger  by  confluence.  They 
are  firm  or  edematous  on  palpation.  ]\Iore  common,  however, 
are  diftuse  swellings  of  the  lower  portion  of  the  head,  ventral 
part  of  the  thorax  and  abdomen,  udder,  prepuce,  or  scrotum 
and  limbs.  In  the  regions  of  the  nostrils  and  lips  they  com- 
monly begin  and  rapidly  extend  upward  toward  the  eyes. 
The  swellings  are  firm,  and,  especially  at  the  flexion  of  joints, 
the  overlying  skin  cracks  open  and  a  yellow,  viscid,  serous 


324         ACUTE  GENERAL  INFECTIOUS  DISEASES 

fluid  exudes,  which  later  (h'ies,  leaving  a  brown  scab.  The 
swellings  terminate  abruptly  ("tied  off")  in  the  head  a  short 
distance  below  the  eyes  and  in  the  limbs  at  the  elbow  and  stifle. 

As  long  as  the  hnnen  of  the  nasal  cavities  and  larynx  is  not 
encroached  upon  by  swellings  the  respirations  are  not  in- 
creased. From  swelling,  especially  of  the  false  nostrils  and 
turbinates,  dyspnea  develops.  If  a  hemorrhagic  or  inflamma- 
tory infiltration  of  the  larynx  api)ear,  ])ronounced  inspiratory 
and  expiratory  dyspnea  with  stertorous  laryngeal  sound  (see 
Glottis  Edema)  follows. 

The  leg  swellings  are  painful,  and  mechanically  interfere 
with  locomotion  and  getting  up  and  down.  Usually  the 
patients  remain  standing  unless  greatly  fatigued  or  the  attack 
mild. 

From  swelling  of  the  head  mastication  is  difficult  or  im- 
possible. If  the  pharynx  is  involved,  blood-tinged  saliva 
drools  from  the  mouth  and  regurgitation  through  the  nostrils 
is  noted.  Food  is  sometimes  retained  between  tlie  teeth  and 
cheeks,  where  it  decomposes  and  emits  a  fetid  odor.  The 
appetite  is  good  in  the  earlier  stages  and  may  be  retained 
throughout  mild  attacks.  If  hemorrhagic  or  inflammatory 
infiltration  of  the  gastro-intestinal  tract  occur,  colic  symptoms 
follow.  The  feces  are  sometimes  blood-stained,  and  diarrhea 
may  set  in  as  a  symptom  of  some  complication  (septicemia). 

The  temperature  is  usually  only  slightl\'  elevated  and  may 
remain  practically  normal  throughout  the  coiu'se  of  the  dis- 
ease, provided  no  complications  occur.  If  c()mi)lications  exist, 
or  the  disease  which  preceded  the  attack  of  purpura  was  a 
feverish  one  and  still  to  a  degree  persist,  the  temperature  is 
elevated.  Purpura  and  the  disease  from  which  it  develops 
may  occur  concomitantly  in  the  sann^  i)atient. 

In  the  early  stages  the  pulse  remains  about  normal.  As  a 
rule  it  rarely  goes  beyond  50  to  (>().  If  it  exceed  80,  compli- 
cations are  ])resent. 

Complications. — (a)  Gangrene  of  tlie  skin  with  sloughing 
is  not  an  uncommon  comi)licati()n.  The  process  of  healing  is 
slow  (sometimes  two  or  three  months),  and  frequently  un- 
sightly scars  are  left  behind,  greatly  reducing  the  market 
value  of  the  horse. 


PURPURA   HEMORRHAGICA— PETECHIAL  FEVER     325 

{b)  Foreign  body  pneumonia:  This  is  apt  to  follow  severe 
pharyngitis,  with  dysphagia,  or  more  rarely  may  be  due  to 
the  aspiration  of  necrotic  pieces  of  mucous  membrane  from 
the  nasal  cavities  and  throat.  Pulmonary  gangrene  usually 
follows,  leading  to  death  in  two  or  three  weeks. 

(e)  Septicemia  usually  attended  by  a  sudden  disappearance 
of  the  symptoms,  profuse  diarrhea,  recumbent  position,  and 
decubitus.    Pulse  is  elevated,  temperature  high. 

(d)  Gastro-enteritis :  Some  cases  begin  with  symptoms  of 
colic  which  yield  to  proper  treatment,  the  purpura  following 
taking  a  benign  course.  If,  however,  large  extravasations 
occur  in  the  stomach,  small  or  large  intestines,  severe  gastro- 
enteritis is  noted.  Necrosis  of  the  extra vasated  areas  in  the 
bowel  may  take  place  and  perforative  peritonitis  result.  The 
patient  presents  violent  colic  symptoms  and  dies  in  twenty- 
four  to  thirty-six  hours. 

Diagnosis. — Purpura  hemorrhagica  is  characterized  by  the 
typical  "  tied-off "  swellings  and  petechia?  in  the  visible  mucous 
membranes.  The  diagnosis  is  easy  if  the  case  is  at  all  typical. 
When  ulcers  occur  in  the  nasal  mucous  membrane  it  might  be 
mistaken  for  acute  glanders.  The  crater-like  margin  an^ 
lardaceous  base  of  the  ulcers,  the  nodules,  star-shaped  cica-» 
trices,  enlargement  of  the  submaxillary  lymph  glands,  and 
the  absence  of  petechise  in  glanders  suffice  to  distinguish  be- 
tween the  diseases.  Glanders  and  purpura  may  both  appear 
in  the  same  patient.  With  malignant  edema  the  disease  would 
rarely  be  confused  (see  this).  Urticaria  could  only  be  mis- 
taken for  purpura  in  the  early  stages  of  the  disease.  Anthrax 
is  a  rare  disease  in  horses  in  the  northern  United  States.  In 
the  South  it  usually  assumes  the  cutaneous  form,  the  swellings 
having  very  little  resemblance  to  purpura.     (See  Anthrax.) 

Course. — Very  varied.  Mild  cases  sometimes  recover  in  less 
than  one  week.  Some  are  attacked  with  violent  sepsis  and  die 
in  two  or  three  days  after  the  first  symptoms  are  observed. 
As  a  rule  a  case  of  this  disease  lasts  two  to  six  weeks,  with 
many  exacerbations  and  remissions.  Recovery  is  sometimes 
rapid  and  unexpected.  Some  patients  give  the  attending 
veterinarian  great  encouragement  until  some  unexpected 
complication  (septicemia,  pneumonia)  occurs  which  leads  to 


326         ACUTE  GENERAL  INFECTIOUS  DISEASES 

(leatli.  Defects  in  the  skin  due  to  ,<;;iii<i'reiie  m;iy  take  luoiiths 
to  heal. 

Prognosis. — The  ])r()<iii()sis  is  generally  (l()iil)tl"iiL  When 
the  swellings  on  the  head  are  extensive  life  is  always  threat- 
ened. A  high  pulse  (80),  diarrhea,  no  aj)i)etite,  constant 
recumbency,  with  attending  decubitus  and  severe  colic,  are 
bafl  symptoms.  The  disai)pearance  of  the  swellings  is  not  a 
good  sign  unless  the  other  symptoms  also  impro\'e.  Blood 
extravasations  may  form  at  any  time  in  any  organ  (bowels, 
brain,  and  spinal  cord),  i)recipitating  sudden  death.  The 
mortality  varies  from  30  to  50  per  cent,  and  is  largely  de- 
pendent on  the  hygienic  surroundings  and  care  of  the  patient. 

Treatment. — As  yet  no  successful  specific  treatment  has 
been  devised  to  combat  the  disease.  The  principal  factor  in 
bringing  cases  to  a  favorable  termination  is  good  hygiene. 
The  patient  should  be  placed  in  a  light,  clean,  well- ventilated, 
bedded  box  stall  and  the  head  halter  removed  (i)revents  ne- 
crosis of  skin  of  face).  In  proj^er  weather  it  may  be  let  run 
out  of  doors  during  the  day.  A  light  blanket  may  be  used  for 
covering.  Allow  plenty  of  clean  water.  The  food  should 
consist  of  oats,  grass,  and  bran  with  plenty  of  salt.  If  there 
is  difficulty  in  swallowing,  gruels  or  milk  may  be  used  or  tube- 
feeding  employed.  The  treatment  is  surgical,  serotherapeutic 
and  medicinal.  The  surgical  treatment  consists  in  a  thorough 
disinfection  of  the  tumefactions,  wounds,  ulcers,  and  abscesses 
(creolin,  lysol  'A  per  cent.).  The  application  of  Burrows' 
solution  with  camphor  (camphor  oiss,  lead  acetat  5vj,  alum 
§iij,  a  tablespoonful  to  a  wine  bottleful  of  water)  is  good  to 
ward  off  gangrene.  Spirits  of  turpentine  applied  two  or 
three  times  is  said  to  have  like  effect.  Scarification  of  the 
swellings  as  usually  i)riictise(l  does  no  good  and  opens  an 
avenue  for  further  infection. 

When  suffocation  threatens,  tracheotomy  should  be  per- 
formed. While  it  no  doubt  prolongs  life,  in  most  cases  where 
called  for  death  follows. 

(jood  results  are  reported  from  the  use  of  antistreptococcic 
serum  in  doses  from  25  to  50  c.c.  It  may  be  given  subcu- 
taneously  and  intratracheally.  Naturally,  its  effect  will  de- 
pend upon  the  presence  of  a  streptococcus  infection  which  is 


HOG  CHOLERA— SWINE  FEVER  327 

by  no  means  proved  in  purpura.  Further,  the  serum  is  ex- 
pensive. Perhaps  some  of  the  good  results  reported  are  due 
less  to  the  potency  of  the  serum  than  to  the  fact  that  when 
used  the  resistance  of  the  patient  is  not  being  reduced  by 
overdrugging,  a  common  practice  before  the  introduction  of 
modern  serum  therapy. 

The  medicinal  treatment  is  very  varied  and  purely  em- 
pirical. The  following  suggests  some  of  the  possibilities  in 
this  regard: 

1 .  Drugs  to  increase  coagulability  of  the  blood : 

(a)  Calcium  chlorid  with  gelatin  (5ss  thrice  daily) 

via  mouth  or  rectum. 
(6)  Turpentine  (Bj  tlirice  daily)  in  pint  of  milk. 
(c)  Adrenalin  (1  pro  mille,  dose  5iv). 

2.  Intestinal  disinfectants: 

(a)  Calomel  (gr.  xx  tlirice  daily) . 
(6)  Ichthyol  in  form  of  sodium  sulpho-ichthyolate 
(5  iiss  tlu-ice  daily) . 

3.  Other  treatments : 

(a)  Intratracheal  injections  of  Lugol's  solution  (§j 

intratracheal) . 
(6)  Collargol  intravenous  (§j  of  a  1.5  per  cent,  solu- 
tion in  water  tlirice  daily). 
Tonic  powders  assist  during  convalescence,  as  artificial 
Carlsbad  salts  to  which  some  powdered  nux  vomica  is  added. 


HOG  CHOLERA.     SWINE  FEVER. 

Definition.- — Hog  cholera  is  a  contagio-infectious  disease  due 
to  a  filterable  virus.  It  assumes  a  variety  of  forms,  but 
primarily  is  a  septicemia  with  secondary  pneumonia,  pleuritis, 
and  diphtheritic  gastro-enteritis.  Clinically,  acute  and  chronic 
types  are  distinguished. 

Occurrence. — The  disease  is  wide-spread,  occurring  in  all 
countries.  It  is  especially  prevalent  in  the  great  corn-belt  of 
the  United  States  in  which  hog-raising  is  extensively  de- 
veloped. The  first  recorded  outbreak  of  hog  cholera  occurred 
in  1833  in  Ohio,  into  which  State  it  was  probably  introduced 


328         ACUTE  GENERAL  INFECTIOUS  DISEASES 

with  imported  hogs  or  bacon  from  Europe.  Following  closely 
in  the  wake  of  the  development  of  transi)ortati()n  facilities,  espe- 
cially railways,  it  spread  from  the  Middle  West  to  all  parts  of 
the  country,  especially  toward  the  West,  where  the  breeding 
of  swine  had  become  a  profitable  industry.  The  losses  from 
cholera  are  enormous,  reaching  as  high  as  $2( )(),()()( ),()()() 
(45,000,000  hogs  infected)  in  1888  and  averaging  close  to 
$50,000,000  annually.  The  farmers  of  the  corn-belt  naturally 
suffer  the  brunt  of  damage  wrought  l)y  the  disease.  Like 
most  infectious  diseases  assuming  an  epizootic  form  the  out- 
breaks come  in  wa^'es.  While  some  years  swine  are  compara- 
tively free  from  the  infection,  or  it  assumes  a  mild  form,  in 
others  it  is  wide-spread  and  especially  malignant.  As  far  as 
is  known,  hogs  are  the  only  animals  which  take  the  disease. 

Etiology. — The  cause  is  an  ultramicroscopic  organism  found 
in  the  blood,  urine,  and  sometimes  in  the  feces  of  cholera-sick 
hogs.  The  parts  i)layed  by  the  Bacillus  suipestifer  and  the 
Bacterium  suisepticum  are  j)robably  incidental,  the  former  in- 
ducing })rincipally  the  chronic  gastro-intestinal  and  the  latter 
the  lung  and  pleural  lesions. 

Natural  Infection. — As  the  organism  of  cholera  is  foimd  in 
the  urine  and  feces,  the  pens,  yards,  etc.,  in  which  sick  hogs 
have  been  kept,  become  contaminated  with  it.  Healthy  but 
susceptible  s^^■ine  become  infected  largely  via  digesti\'e  tract 
through  food  and  water  polluted  with  the  secretions  and 
excretions  of  the  diseased.  Hog  cholera  is  introduced  into  a 
non-infected  farm  as  follows: 

1.  By  infected  hogs:  These  may  stray  from  neighboring 
infected  herds,  be  borrowed  (breeding  boars),  brought  in  by 
purchase,  or  show-swine  returned  from  fairs,  expositions,  etc., 
may  bring  the  infection  home.  Hogs  introduced  during  the 
incubative  stage  of  the  disease.  Such  swine  may  seem  healthy 
at  the  time  of  purchase,  but  a  few  days  later  the  symptoms 
appear.  Hogs  suffering  from  cholera  in  a  chronic  form 
("germ  carriers"),  esi)ecially  old  breeding  boars  and  sows, 
showing  no*  ty])ical  symptoms. 

2.  The  infection  may  also  be  i)r()ught  into  the  premises  by 
such  intermediary  agents  as  stray  dogs,  crows,  fowls.  Per- 
sons can  also  carr^■  it  on  their  boots  and  clothing.     Once  the 


HOG  CHOLERA— SWINE  FEVER  329 

disease  breaks  out  it  is  spread,  as  noted,  by  the  urine,  feces, 
and  other  discharges  of  the  sick,  and  by  careless  disposition 
of  the  dead  (throwing  carcasses  into  water-ways  or  leaving 
them  on  the  fields;  too  shallow  burial,  incomplete  cremation, 
etc.).  Hauling  the  carcasses  in  wagons  through  the  premises 
and  along  the  roadways  is  a  further  factor  in  the  spread  of  the 
disease.  It  is  a  common  practice  when  hog  cholera  is  dis- 
covered to  exist  on  a  farm  for  the  owner  to  attempt  getting 
rid  of  the  disease  by  selling  those  hogs  which  are  in  a  market- 
able condition.  Too  often  a  close  discrimination  between 
the  infected  and  uninfected  is  not  made.  In  transit  or  soon 
after  arrival  at  their  destination  the  disease  may  break  out, 
infecting  the  railway  cars,  shutes,  pens,  etc.  Hog  cholera, 
therefore,  is  spread  over  great  areas,  and  especially  along 
lines  of  traffic. 

A  transmission  of  the  disease  along  the  course  of  a  flowing 
stream  is  probable,  the  current  carrying  the  infection. 

Necropsy. — (a)  Septicemic  Form. — Lesions,  as  in  hemor- 
rhagic septicemia.  Petechise  and  ecchymoses  of  the  skin, 
serous  membranes  and  of  the  mucous  membranes  of  the 
gastro-intestinal  tract,  especially  of  the  bowels.  In  the  latter, 
accumulations  of  clotted  blood  may  be  found;  the  lymph 
glands  are  swollen  and  blood-shot;  the  parenchymatous 
organs  congested,  the  spleen  little  if  at  all  swollen.  The 
petechise  over  the  kidneys  give  them  a  spotted  appearance, 
known  as  "turkey-egg"  kidney.  On  the  serous  membranes 
fibrinous  exudates  appear;  catarrh  of  the  stomach  and  small 
intestine  is  also  noted. 

(b)  The  Intestinal  Form. — The  most  characteristic  lesions 
are  noted  in  the  large  bowels,  especially  in  the  cecum.  There 
appear  in  the  mucosa  and  submucosa,  flat,  round,  hard, 
elevated,  yellowish,  greenish-yellow  or  gray  areas  of  necrosis. 
The  areas  vary  in  size  from  a  pin-head  to  a  twenty-five-cent 
piece.     They  are  commonly  known  as  "button  ulcers." 

(c)  Pectoral  Form. — The  lungs- present  the  signs  of  pneu- 
monia (croupous,  catarrhal  or  mixed)  with  serofibrinous 
pleuritis  and  pericarditis.  In  subacute  or  chronic  cases 
multiple  necrotic  foci  are  present  in  the  lung  with  caseation 
which  may  in^'olve  the  lymph  glands. 


330         ACUTE  GENERAL  INFECTIOUS  DISEASES 

The  f()ll()\vin<f  lu'cropsy  lesions  speak  tor  hot::;  cliolcra  in 
outbreaks  occurring  in  tlie  United  States: 

(a)  Petechia'  and  ecchymoses  of  skin. 

(b)  I'etechitie  and  eccliymoses  of  serous  membranes,  espe- 
cially of  the  pleura,  epicardium  and  ])eritoneum  over  the 
kidneys  ("turkey-egg  kidney"). 

(c)  Swollen  lymph  glands. 

(d)  Button  ulcers  in  the  bowel  (especially  cecum  and 
colon) . 

(e)  Absence  of  pronounced  splenic  enlargement.  (In 
subacute  and  chronic  cases  the  spleen  may  be  smaller  than 
normal.) 

Symptoms. — The  period  of  inculcation  \aries  from  four  to 
eighteen  days,  usually  it  is  eight  to  ten  days.  The  symptoms 
of  hog  cholera  are  not  particularly  characteristic.  In  the 
beginning  of  an  outbreak  the  first  warning  given  is  the  finding 
of  a  dead  hog  in  the  herd.  Later  another  may  be  found. 
These  losses  may  continue  for  a  week  or  so  when  a  number  of 
swine  show  signs  of  disease.  The  symptoms  will  vary  with 
the  outbreak  and  the  individual,  /.  e.,  some  cases  showing  the 
pulmonary,  others  the  intestinal  type  of  the  disease,  etc.,  as 
follows : 

(a)  Septicemic  Furvi. — Barring  peracute  cases  which  die 
suddenly  without  ha\'ing  shown  marketl  symptoms,  the  hog 
with  acute  cholera  loses  appetite,  seems  sluggish,  weak,  and 
is  apt  to  crawl  off  in  a  corner  or  buries  itself  in  the  straw-pile. 
They  usually  do  not  come  to  feed  when  called,  and  if  driven 
out  of  their  seclusion  are  disinclined  to  move,  hold  the  back 
arched,  the  curl  is  gone  from  the  tail,  and  the  ears  droop. 
On  the  surface  of  the  abdomen,  the  inside  of  the  thighs,  and 
around  the  ears  and  neck  smaller  i^ctechia'  or  larger  ecchy- 
moses are  noted.  A  quite  c-haracteristic  symi)tom  is  con- 
junctivitis, the  exudate  causing  the  lids  to  adhere.  Vomiting 
is  not  uncommon.  At  first  the  bowels  are  constipated,  but 
later  diarrhea  sets  in,  the  feces  being  often  blood-stained. 
The  temperature  is  high. 

(6)  Bowel  Form. — This  type  of  cholera  involves  not  only 
the  intestines  but  the  whole  digestive  tract.  The  symptoms 
either  ff)llow  those  of  the  septicemic  form  or  may  come  on 


HOG  CHOLERA—SWINE  FEVER  331 

more  gradually.  They  consist  in  a  tliphtheritic  stomatitis 
and  pharyngitis,  leading  to  dysphagia,  and  if  the  larynx 
becomes  involved,  pronounced  dyspnea.  Sometimes  in  cases 
with  prolonged  course  on  palpation  tumefactions  due  to 
enlarged  lym})h  glands  and  adhering  bowel  loops  (adhesive 
peritonitis)  may  be  felt  tlirough  the  abdominal  wall.  The 
hogs  eat  little  or  nothing  and  show  diarrhea  alternating  with 
constipation.  The  patients  move  sluggislily,  arch  the  back 
and  lie  down  most  of  the  time.  Under  symptoms  of  anemia, 
cachexia  and  general  debility  death  follows  in  two  or  tliree 
weeks.     A  few  cases  recover,  but  usually  remain  stunted. 

(c)  Pectoral  Form. — In  this  form  the  symptoms  of  pneu- 
monia and  pleuritis  predominate.  The  hogs  show  high  fever 
(108°  F.),  and  cough  frequently.  There  is  often  pronounced 
expiratory  dyspnea  and  nasal  discharge.  Conjunctivitis  is 
present.  In  the  skin  of  the  ears,  neck,  sides  and  lower  por- 
tions of  the  body,  tail,  etc.,  appear  petechi?e  and  ecchymoses. 
The  bowels  are  constipated  in  the  beginning  but  later  diarrhea 
sets  in.  Death  usually  results  in  one  or  two  weeks,  although 
in  a  few  cases  the  disease  becomes  chronic,  leading  to  emacia- 
tion, capricious  appetite,  cough,  dyspnea  and  fetid  diarrhea. 
Death  may  follow  in  one  or  two  months  from  exhaustion. 
Occasionally  an  encapsulement  of  necrotic  lung  foci  takes 
place  and  the  patient  recovers. 

{d)  Mixed  Form. — While  in  the  beginning  of  outbreaks 
of  hog  cholera  the  disease  may  assume  one  of  the  above- 
described  forms,  usually  later  both  the  lung  and  bowel  types 
occur  concomitantly  in  the  individual.  The  symptoms  are 
therefore  quite  complex,  but  usually  one  or  the  other  form 
predominates.  In  many  outbreaks  marked  skin  lesions 
appear.  Besides  the  intravascular  redness  noted,  vesicles, 
pustules,  ulcers,  and  marked  necrosis,  especially  of  the  ears 
and  tail  (which  may  drop  off),  occur.  Not  infrequently 
urticaria  and  loss  of  the  bristles  are  observed. 

Diagnosis. — The  diagnosis  of  cholera  intra  vitam  is  difficult, 
especially  in  the  beginning  of  an  outbreak.  Usually  after 
carefully  weighing  the  available  symptoms  an  examination 
postmortem  (see  this)  must  be  made.  In  case  of  doubt  a 
diagnosis  can  only  be  made  by  inoculating  healthy  young 


332         ACUTE  GENERAL  INFECT  10 US  DISEASES 

swine  with  the  filteretl  blood  of  the  suspect.    I  lo^  choleni  nia\' 
be  confused  with: 

(a)  Swill  ChoJcrn. — In  districts  free  from  lio^'  cholera  a 
disease  appears  very  like  cholera.  It  is  due  to  feeding  swill 
containinji;  dishwater  in  which  is  a  quantity  of  powdered  soap. 
Even  the  postmortem  lesions  resemble  those  of  cholera. 
Careful  inquiry  into  the  mode  of  feeding  usually  suffices  to 
ex])lain  the  origin  of  the  disease  which  promptly  disappears 
when  the  food  is  changed.  Hog  cholera,  howe\'er,  commonly 
breaks  out  among  swine  fed  kitchen  offal  from  large  institu- 
tions (penitentiaries,  asylums).  The  food  in  these  cases  is 
not  the  cause.  Large  numbers  of  hogs  are  bought  up  indis- 
criminately to  consume  this  waste,  and  with  them  a  few 
which  either  have  cholera  in  a  chronic  form  or  are  cholera 
convalescents  ("germ  carriers"). 

(h)  Tuhcmdosis. — This  is  a  common  disease  of  swine  which 
follow  tubercular  cattle,  are  fed  skim  milk  containing  tul)ercle 
bacilli,  or  the  tubercular  ofi'al  from  slaughter  houses.  It  would 
be  confused  only  with  chronic  cholera.  The  history  and  ne- 
cropsy nearly  always  suffice  to  differentiate  between  the  two 
diseases.  In  cases  of  doubt  the  bacteriological  examination 
(staining  for  tubercle  bacilli)  may  be  employed. 

(c)  Lnng-worms  (Strongylus  Paradoxus). — These  thread- 
worms are  sometimes  found  in  the  bronchi  of  young  pigs. 
They  induce  chronic  cough  and  general  unthriftiness.  Occa- 
sionally death  is  induced  through  pulmonary  edema.  A 
necropsy  reveals  absence  of  cholera  lesions  and  the  presence  of 
the  strongylus  in  the  foamy  mucus  of  the  small  bronchi. 

Prognosis. — The  prognosis  varies  with  the  outbreak.  In 
some  years  the  disease  assumes  a  mild  form  leading  to  a 
mortality  of  not  over  1  (>  to  20  ])er  cent. ;  in  others  it  may  reach 
80  to  100  per  cent.  The  sei)ticemic  form  is  nearly  always 
fatal.  The  pectoral  type  leads  to  the  death  of  all  swine 
showing  marked  ]:)ulmonary  symptoms  ((lysi)nea,  cyanosis, 
etc.).  While  recoNcries  in  the  intestinal  form  are  not  un- 
common, convalescence  is  often  jjrolonged  which  greatly 
alfects  the  value  of  the  hog.  The  same  is  true  of  chronic 
cases  which  seldom  regain  their  former  thrifty  condition. 
An  exception  is  formed  in  old  breeding  boars  and  sows. 


CATTLE  PLAGUE— RI N DEEPEST  333 

Treatment. — A  medicinal  treatment  is  useless  in  hog 
cholera.  Once  the  disease  has  broken  out  it  is  usually  recom- 
mendable  to  kill  all  swine  showing  intensive  symptoms.  The 
carcasses  should  be  rendered  harmless  by  cremation  or  deep 
burial.  A  thorough  disinfection  should  follow,  viz.,  all  litter, 
droppings,  etc.,  should  be  burned.  Feed  troughs,  sheds,  hog 
houses,  etc.,  disinfected  (cresol  3  per  cent.).  Lime  should  be 
scattered  abundantly.  Hogs  which  show  mild  symptoms  or 
are  carrying  temperature  should  be  inoculated  with  Dorset 
serum  (obtainable  from  some  State  experiment  stations, 
agricultural  colleges,  livestock  sanitary  boards,  but  not  from 
the  Bureau  of  Animal  Industry).  There  are  two  ways  of 
applying  this  serum:  one  known  as  the  "serum  alone" 
method,  used  in  infected  hogs,  and  the  "simultaneous 
method,"  serum  and  virulent  blood  being  injected  simulta- 
neously into  the  medial  aspects  of  the  thighs  of  swine  which 
show  no  symptoms  of  the  disease  and  carry  no  fever. 


CATTLE  PLAGUE.     RINDERPEST. 

Definition. — Cattle  plague  is  a  very  fatal  contagious  disease 
of  cattle  and  buffalo  of  Oriental  countries,  which  is  character- 
ized by  a  se\'ere  croupous  and  diphtheritic  inflammation  of 
the  mucous  membranes,  especially  of  the  digestive  tract.  It 
sometimes  in^'olves  the  outer  skin. 

Occurrence. — Cattle  plague  never  existed  in  the  United 
vStates.  "While  formerly  it  was  generally  distributed  through- 
out France,  Germany,  England,  at  the  present  time,  except 
for  the  Balkan  peninsula,  Europe  is  free  from  it.  The  dis- 
ease is  common  in  Africa  and  Asia,  however,  where  it  is  today 
notoriously  prevalent  in  Russia  and  the  Philippine  Islands. 
The  disease  is  rare  in  sheep  and  camels  which  offer  consider- 
able resistance  to  inoculation.  vSolipeds  and  carnivora  are 
naturally  immune. 

Etiology. — Cattle  plague  is  due  to  an  ultramicroscopic  virus 
found  in  the  blood,  tissue  fluids,  exudates  and  in  the  secretions 
and  excretions  (bile,  urine,  feces,  saliva,  tears,  sweat)  of  the 
bodv  of  an  infected  animal.      The  virus  is  not  modified  by 


334         ACUTE  GENERAL  INFECTIOUS  DISEASES 

rei)eat('<l  ])assing  throiiii;li  cattle,  although  passage  tlirough 
sheep  and  goats  is  said  to  weaken  it. 

Natural  Infection. — Takes  place  by  direct  contact  with 
infected  animals  or  indirectly  through  hides,  meat  or  dis- 
eased secretions  and  excretions,  attendants,  clothing,  food, 
water,  and  stable  utensils.  The  disease  is  readily  spread 
along  avenues  of  transportation  by  animals  which  have  it  in 
a  mild  form.  The  mode  of  infection  is  usually  through  the 
digestive  tract.  Transmission  through  the  air  does  not  seem 
probable,  as  inclosing  an  infected  patient  by  a  fence,  ditch  or 
even  a  tight  stall  partition  suffices  to  prevent  the  further 
spread  of  the  disease.  One  attack  generally  lends  immunity 
for  an  indefinite  period. 

Necropsy. — The  postmortem  changes  vary  somewhat  with 
the  severity  and  duration  of  the  attack.  Most  conspicuous 
are  the  lesions  in  the  mucous  membranes  which  are  swollen, 
reddened,  show  petechia:',  croupous,  and  diphtheritic  areas. 
The  cadaver  is  usually  much  emaciated  and  commonly  an 
accumulation  of  a  mucopurulent,  yellow  or  discolored  dis- 
charge is  found  at  the  natural  openings.  The  mucous  mem- 
brane of  the  mouth  and  pharynx  shows  petechia?,  croupous 
deposits  and  ulcers,  most  pronounced  in  the  inner  surface  of 
the  lips,  under  the  tongue,*along  the  gums  and  cheeks.  While 
the  rumen,  reticulum,  and  omasum  present  no  characteristic 
changes,  the  mucosa  of  the  abomasum  is  swollen,  highly 
reddened,  and  covered  with  a  viscid,  dark-colored  exudate. 
In  some  cases  erosions  appear.  In  the  duodenum  and  ileum, 
Peyer's  plaques  and  the  solitary  follicles  are  swollen,  dark  red 
in  color,  and  infiltrated  with  purulent  exudate.  The  changes 
noted  in  the  large  intestine  are  similar  though  usually  less 
marked.  The  intestinal  contents  are  soft  and  of  a  reddish- 
brown  color.  The  spleen  is  rarely  enlarged;  it  is  usually 
anemic  and  smaller  than  normal.  The  liver  is  very  light 
colored,  anemic,  and  very  friable.  The  gall-l)ladder  is  greatly 
distended  with  a  light  green,  watery  or  dark-colored  bile. 
The  respiratory  tract  shows  catarrhal  rliinitis  with  edema  of 
the  submucosal  ulcerous  erosions  and  croupous  pseudomem- 
branes  are  common.  The  lungs  are  edematous,  sometimes 
contain  catarrhal  pneumonic  foci,  and  frequently  interstitial 


CATTLE  PLAGUE—RINDERPEST  335 

emphysema.  The  blood  is  dark  and  coagulates  feebly.  In 
some  outbreaks  a  peculiar  nodular  and  pustular  eruption  is 
found  on  the  skin. 

Symptoms. — The  period  of  incubation  is  three  to  nine  days. 
The  first  symptom  is  that  of  fever,  the  temperature  ranging 
from  104.9°  to  107°  ¥.,  falling  somewhat  in  the  next  few  days 
and  becoming  subnormal  shortly  before  death.  The  affected 
cattle  are  Very  languid,  the  whole  musculature  relaxed,  the 
head  held  down,  ears  pendent,  back  arched,  and  a  tendency 
to  knuckle  in  the  hind  fetlocks  is  noticeable.  The  hair  coat  is 
roughened  and  involuntary  twitching  of  the  muscles  of  the 
head,  shoulders,  and  flanks  is  frequent.  In  some  patients 
there  is  a  pronounced  chill  lasting  several  minutes.  A  com- 
mon early  symptom  is  a  frequent,  painful  cough  which  disap- 
pears as  the  severe  gastro-enteritis  develops.  The  patients 
are  usually  dyspneic.  From  the  nose  flows  a  mucopurulent 
(rarely  bloody)  discharge  mixed  with  saliva,  which  excoriates 
the  skin  of  the  nostrils. 

The  conjunctiva  is  either  anemic  or,  on  the  contrary,  it  may 
be  congested,  the  lids  closed  and  swollen,  tears  flowing  down 
the  cheeks.  Later  there  develops  a  purulent  discharge  which 
dries  to  form  crusts  about  the  eyelids.  Keratitis  may  be 
present.  In  the  mouth  the  gums  are  swollen  and  dark  blue 
or  dirty  red  in  color.  On  the  inner  surface  of  the  lips  irregu- 
lar, shallow  erosions  are  noted.  Commonly  the  mucous  mem- 
brane of  the  mandible  and  of  the  dental  pad  becomes  covered 
with  yellow  granules  as  if  sprinkled  with  corn  meal.  These 
areas  later  become  confluent  and  slough,  leaving  behind 
readily  bleeding  ulcers.  In  swine  outbreaks  the  mouth 
lesions  are  little  developed. 

While  in  the  initial  stage  the  bowels  are  constipated,  after 
the  second  day  a  profuse  diarrhea  sets  in,  the  liquid  feces 
are  mixed  with  blood  and  fibrinous  clots.  The  patients  lose 
flesh  rapidly.  In  some  outbreaks  there  appear  in  the  skin  of 
the  udder  or  scrotum,  inner  surface  of  the  thighs,  around  the 
vulva  and  nose  a  nodular  and  pustular  exanthema.  In  milch 
cows  lactation  stops,  the  udder  becoming  relaxed  and  smaller. 
The  pulse  varies  from  50  to  100.  From  the  vulva  in  some 
cases  there  is  a  dirty  mucopurulent  discharge  from  the 
inflamed  mucosa. 


336         ACUTE  GENERAL  INFECTIOUS  DISEASES 

Diagnosis.  The  recognition  of  the  first  cases  of  cattle 
plague  is  difficult.  The  disease  is  characterized  by  its  sudden 
appearance,  the  rapid  development  of  the  symptoms  and  the 
peculiar  lesions  found  on  the  visible  mucous  meml)ranes.  Of 
great  importance  is  a  clear  history  of  the  origin  of  the  out- 
break and  the  opportunity  jiresented  for  the  disease  to  be 
introduced  on  the  premises.  ( 'attle  plague  may  be  confused 
with  the  following: 

Malkjnani  Head  Catarrh. — Here  while  the  mucous  mem- 
branes of  the  head  (eyes,  nose)  are  severely  involved,  the 
digestive  and  genital  tracts  are  mildly  involved.  Keratitis  is 
more  pronounced  in  this  disease.  Further,  malignant  head 
catarrh  occurs  s])oradically  and  is  not  contagious. 

Foot-and-mouth  Disease. — \Yould  only  be  confused  with 
cattle  plague  when  the  mouth  erosions  following  the  rupture 
of  the  vesicle  were  deep  and  covered  with  a  pseudomembrane 
and  gastro-enteritis  was  present.  Foot-and-mouth  disease, 
however,  is  characterized  by  vesicle  formation,  affects  the 
feet  and  usually  does  not  involve  the  eyes  and  nose.  Its 
spread  is  further  much  more  rapid  than  the  cattle  plague. 

Course. — The  course  is  usually  five  to  seven  days,  ending  in 
deatli.  Toward  the  end  of  an  outbreak  a  few  cases  may 
recover. 

Prognosis. — The  prognosis  is  l)ad,  SO  to  90  per  cent,  of  the 
cases  prove  fatal.  In  the  gray  cattle  of  the  Russian  steppes 
the  mortality  is  not  over  50  per  cent. 

Treatment. — Medicinal  treatment  is  of  no  value.  Good 
results  are  recorded  from  the  use  of  anti-Rinderpest  serum 
coupled  with  a  strict  sanitation. 

Prophylaxis. — In  civilized  countries  cattle  plague  has  been 
stamped  out  by  the  compulsory  slaughter  of  all  animals 
affected  and  the  enforcement  of  strict  quarantine  measures 
against  infected  districts.  As  the  disease  is  not  transmitted 
any  distance  through  the  air,  its  eradication  is  not  difficult 
when  cooperation  on  the  part  of  the  cattle  owners  can  be 
obtained.  The  period  of  quarantine  should  extend  ten  days 
after  the  last  patient  has  died  or  been  killed.  Carcasses 
should  f)e  disposed  of  as  in  anthrax. 

Protective  Inoculation. — As  on<*  attack  of  cattle  plague 
confers  lasting  inununity,  ett'orts  ha\e  been  made  to  protect 


AFRICAN  HORSE-SICKNESS— PESTIS  EQUORUM    337 

against  it  by  inoculating  healthy  cattle  with  various  secre- 
tions (bile,  nasal  discharge,  tears),  blood  serum  and  blood 
from  affected  animals.  The  inoculated  animals,  however, 
can  spread  the  disease  which  has  led  to  considerable  losses 
where  the  method  of  vaccination  has  been  practised.  In 
badly  infected  districts,  like  South  Africa,  however,  fair 
results  have  been  obtained.     (For  details  see  larger  works.) 

AFRICAN  HORSE-SICKNESS.     PESTIS  EQUORUM. 

Definition. — African  horse-sickness  is  an  infectious  disease 
of  solipeds  due  to  an  ultramicroscopic  virus.  It  is  charac- 
terized by  extensive  edematous  swellings  under  the  skin  and 
hemorrhages  in  the  internal  organs. 

Occurrence. — The  disease  is  indigenous  to  South  Africa 
where  it  occurs  epizootically  and  leads  to  enormous  losses 
among  horses  and  mules.  It  therefore  attains  economic 
importance. 

Etiology. — The  cause  is  a  filterable  virus.  The  blood  of  a 
horse  affected  with  the  disease  will  readily  transmit  it  to 
susceptible  animals  no  matter  what  way  the  inoculation  is 
attempted.  The  manure  is  thought  not  to  be  infectious.  It 
does  not  seem  possible  to  infect  animals  other  than  horses, 
asses  and  mules,  although  Angora  goats  have  been  success- 
fully inoculated. 

Natural  Infection. — The  disease  appears  during  the  warm, 
rainy  months  of  January,  February,  and  March.  It  disap- 
pears after  the  first  frost.  Horses  on  pasture  during  these 
months  are  most  often  aff'ected.  The  night  season  is  more 
dangerous  than  the  daytime  in  this  regard.  Probably  the 
infection  is  carried  by  insects  (mosquitoes,  anopheles,  stego- 
myia).  Keeping  a  fire  smudge  near  horses  on  pastiu-e  at 
night  or  protection  with  mosquito  netting  is  said  to  prevent 
the  infection. 

Necropsy. — Gelatinous  infiltration  of  the  subcutaneous  and 
intramuscular  connective  tissue  about  the  eyes  and  tliroat  is 
commonly  noted.  Evidence  of  gastro-intestinal  catarrh  or  in 
some  cases  hemorrhage  and  ulceration  of  the  intestine  is  a 
common  finding.  The  serous  membranes  show  petechia^  and 
22 


338         ACUTE  GENERAL  INFECTIOUS  DISEASES 

not  infrequently  fibrinous  exudation.  The  lungs  are  edema- 
tous, the  spleen  is  normal  and  the  liver  and  kidneys  congested 
or  inflamed.     The  superficial  lymph  glands  are  enlargefl. 

Symptoms. — The  period  of  incubation  is  about  one  week. 
Four  forms  of  the  disease  are  described  from  a  clinical  stand- 
point: The  peracute,  acute,  subacute,  and  chronic.  The  most 
important  are  the  acute  and  subacute  forms. 

(ft)  Acute  Form. — This  form,  known  in  Africa  as  Dunko- 
pziekte,  begins  with  a  high  fever  (104°  to  107.0°  F.),  dyspnea, 
pulmonary  edema,  and  heart  paralysis.  Death  usually  occurs 
in  one  or  two  weeks. 

(b)  Subacute  Form. — The  subacute  form,  known  as  Dikko- 
pziekte,  takes  a  longer  and  milder  course.  Characteristic  of 
this  form  is  a  marked  swelling  of  the  head,  principally  about 
the  eyes;  swelling  and  prolapses  of  the  tongue  which  is 
markedly  cyanotic.  From  this  symptom  the  name  Blaw 
tong  (blue  tongue)  is  given  the  disease.  The  patient  shows 
marked  muscular  weakness.  In  this  form  the  majority  of 
the  cases  recover. 

The  peracute  or  apoplectic  form  i)roduces  sudden  death; 
the  chronic  form  assumes  an  atypical  course  lasting  for  weeks 
and  resembling  infectious  anemia. 

Treatment. — A  medicinal  treatment  has  to  date  not  ])roven 
satisfactory.  Internally  large  doses  of  creolin  have  been 
recommended. 

Prevention. — Pre^'ention  consists  in  keeping  the  horses  off 
infected  or  suspected  pastures  during  the  night  time  or  driv- 
ing them  to  higher  altitudes  during  the  dangerous  months 
of  the  year.  Fairly  good  results  have  been  obtained  by  pre- 
ventive inoculation  to  produce  immunity.  As  in  hog  cholera 
a  combined  virus  and  serimi  vaccination  is  practised. 

Heartwater. — Definition. — Ilcartwater  is  a  disease  which  is 
not  identical  with  horse-sickness.  It  is  a  contagio-infectious 
hydropericardium  of  cattle,  sheep  and  goats  of  the  Trans\'aal. 
The  disease  is  carried  by  ticks  ( Amblyomma  hebrt^um) . 


CHAPTER  11. 
ACUTE  EXANTHEMATOrS  INFECTIOUS  DISEASES. 

VARIOLA.     POX. 

Definition. — Variola  is  an  acute  contagious  disease  char- 
acterized by  a  typical  cutaneous  eruption  which  passes 
through  the  stages  of  papule,  vesicle,  pustule,  and  crust.  In 
all  animals  except  sheep  this  eruption  is  usually  local. 

Occurrence. — ^^Yhile  cow-pox  is  a  very  common  disease  in 
the  United  States,  horse-pox  is  rare  and  sheep-pox  has  never 
been  reported.  In  Asia,  Africa  and  in  parts  of  Europe 
sheep-pox  becomes  epizootic,  causing  great  losses. 

Etiological  Relationship. — The  etiological  relationship  of  the 
pox  of  the  different  animals  and  of  man  to  one  another  is  not 
yet  clear.  There  is  undoubtedly  a  close  relationship  between 
cow-pox  (variola  vaccina)  and  smallpox  of  man  (variola 
humana),  although  if  man  be  inoculated  with  cow-pox,  the 
eruption  resulting  usually  remains  local.  Further,  cattle  are 
not  readily  inoculated  with  smallpox.  However,  as  is  well 
known,  if  man  be  inoculated  (vaccinated)  with  cow-pox,  he  is 
protected  against  smallpox.  Sheep-pox  is  transmitted  with 
difficulty  to  either  man  or  cattle,  natural  infection  does  not 
occur  and  no  protection  agaiinst  cow-pox  is  afforded  cattle 
inoculated  with  sheep-pox  virus.  Sheep-pox  therefore  is 
probably  a  specific  disease  of  sheep  which  does  not  spread  to 
other  animals  including  goats.  Goat-pox  affects  neither  man 
nor  sheep  and  seems  to  be  a  specific  caprine  disease.  Horse- 
pox  is  a  local  disease  of  the  skin  in  the  region  of  the  fetlocks. 
It  is  probably  closely  related  to,  if  not  identical,  with  cow-pox, 
being  transmitted  by  recently  vaccinated  horseshoers  to 
horses  while  being  shod.  In  the  light  of  our  present  knowl- 
edge smallpox  (variola  humana),  sheep-pox  (variola  ovina) 
and  goat-pox  (variola  caprina)  are  independent  diseases,  while 


340    ACUTE  EXANTHEMATOUS  INFECTIOUS  DISEASES 

the  pox  of  other  animals  (ox,  horse,  swine)  are  merely  modi- 
fications of  these. 

It  is  extremely  probable  that  in  the  beginning  all  forms  of 
variola  had  a  common  origin.  By  continued  passage  for 
several  generations  through  different  species  of  animals,  how- 
ever, the  virus  has  become  so  adapted  to  the  specific  species 
in  which  it  has  propagated,  that  transmissability  to  other 
species  of  animals  no  longer  occurs  through  natural  infection 
and  is  difficult  to  bring  about-by  inoculation. 

Etiology. — From  recent  experiments  it  has  been  determined 
that  filtering  the  \'irus  of  the  variola  of  different  animals  and 
man  does  not  decrease  its  virulency  imless  very  fine  filters 
are  employed.  It  is  probable,  therefore,  that  the  cause  is  an 
ultramicroscopic  organism . 

The  virus  is  contained  in  the  papule,  vesicles,  and  crusts. 
It  is  doubtful  whether  the  expirium  or  blood  of  the  varioloid 
patient  is  infectious.  The  secretions  and  excretions  are  in- 
fective when  contaminated  with  the  contents  of  the  vesicles. 

Sheep-pox  (Variola  Oviiia). — Definition. — A  specific  infec- 
tious disease  of  sheep  characterized  by  a  cutaneous  eruption 
which  passes  through  the  stages  of  papule,  vesicle,  pustule, 
and  crust. 

Occurrence. — Sheep-pox  is  not  known  in  the  United  States. 
^Vhile  its  home  is  in  Asia,  outbreaks  have  occurred  in  Europe 
and  Africa.  When  the  disease  becomes  epizootic  it  causes 
considerable  economic  losses  from  death  and  the  damage  it 
causes  the  wool. 

Etiology. — Tlic  cause  is  probably-  an  ultramicroscopic 
organism. 

Natural  Infection. — The  virus  enters  through  the  respiratory 
tract  and  is  carried  from  the  lung  alveoli  by  the  blood  to  the  skin 
and  mucous  membranes.  Intratracheal  injections  of  the  con- 
tents of  the  vesicles  (lymph)  readily  produce  the  disease, 
while  feeding  experiments  have  negative  results  provided 
inhalation  was  excluded.  lmi)rcgnating  the  air  a  distance 
from  susceptible  shcc]>  with  a  spra\'  of  j^ox  lymi)h  or  the 
dried  crusts  gave  positive  results. 

A  flock  of  sheep  is  usually  infected  by  direct  contact  with  a 
variolous  sheep,  one  convalescent  from  the  disease,  and  in 


VARIOLA— POX  341 

countries  where  protective  inoculation  is  practised,  from  a 
vaccinated  lamb.  In  rarer  instances  the  contagion  is  trans- 
mitted through  intermediary  agents  (pelts,  wool,  food,  bed- 
ding, clothing  of  attendants,  etc.).  During  the  crust  and 
desquamative  stages  of  the  disease  the  affected  sheep  are 
especially  dangerous  to  susceptible  ones.  As  the  wool  will 
retain  the  desquamated  scales  for  several  wrecks,  the  disease 
may  be  spread  by  a  sheep  fully  recovered  from  variola,  the 
infection  being  carried  in  the  fleece.  Lambs  are  much  more 
susceptible  than  adult  sheep. 

Intra-uterine  infection,  the  lamb  being  born  with  the  dis- 
ease, is  not  rare.  In  other  instances  the  lamb  born  of  a  vari- 
olous ewe,  comes  into  the  world  healthy  but  is  an  immune. 
The  period  of  incubation  is  about  one  week  except  in  cold 
weather  when  it  may  be  longer. 

Symptoms. — Preceding  the  eruption  there  is  commonly 
fe\'er  (105°  to  107°  F.),  languor,  catarrhal  conjunctivitis  and 
rhinitis,  loss  of  appetite  and  suppressed  rumination.  The 
patients  seem  stiff  and  extremely  sensitive  over  the  back  and 
loins.  In  one  or  two  days  on  different  parts  of  the  skin 
usually  not  covered  by  wool  (eyes,  inner  surface  of  the  thighs, 
chest,  abdomen,  under  the  tail)  small,  dark  red-colored,  flea- 
bite-like  spots  (papules)  appear  which  in  three  to  five  days 
develop  into  lentil-sized  blisters  (vesicles)  filled  with  a  clear 
fluid.  The  vesicles  often  present  a  depression  in  the  centre 
(umbilicated)  while  some  are  simply  flattened  on  top.  About 
the  seventh  daj'  after  the  appearance  of  the  eruption  the 
contents  of  the  vesicles  become  turbid,  containing  pus 
(pustule).  Usually  three  days  later  the  pustules  erupt  and 
dry,  forming  in  the  edematously  infiltrated,  reddened  skin 
about  them  firm  gray  scabs  which  later  become  brown  in 
color.  The  scabs  in  three  to  five  days  become  detached, 
leaving  a  pit.  All  the  vesicles  do  not  appear  at  the  same 
time,  but  continue  to  form  at  intervals,  materially  prolonging 
the  course  of  the  exanthema  in  the  individual  which  may 
present  all  the  successive  stages  of  the  eruption  at  the  same 
time.  The  temperature  which  is  high  during  the  prodromal 
stage,  falls  when  the  eruption  develops  but  rises  again  when 
the  pustules  form  (secondary  infection) .     When  the  pustules 


342     ACUTE  EXANTHEMATOUS  INFECTIOUS   DISEASES 

erupt  the  temperature  becomes  normal.  The  odor  of  sheej)- 
pox,  which  is  pecuharly  sweetish  and  nauseating,  is  ([uite  (Hs- 
tinctive.  It  is  most  marked  in  tlie  early  stages  and  often  of 
diagnostic  value. 

The  eruption  also  appears  in  the  mucous  membranes,  pro- 
ducing when  in  the  mouth,  ptyalism;  throat,  dysphagia; 
l)owel,  diarrhea,  and  in  the  bronchi,  cough. 

The  following  modifications  in  sheep-pox  are  observed: 

(a)  Abortive,  Mild  Type. — Either  no  eruption  appears  in  the 
skin  or  only  a  very  few  isolated  lesions  as  in  "varioloid"  of 
man.  The  general  disturbance  is  not  marked  and  the  course 
benign. 

(6)  No  vesicles  form,  the  reddish  pai)ules  in  a  few  days 
becoming  detached  and  disappearing. 

(c)  Confluent  Fox. — This  is  a  more  severe  form,  the  pustules 
occurring  ^'ery  close  together  and  finally  blending.  It  is 
most  marked  on  the  head,  the  skin  of  A\'hich  ])ecomes  swollen 
and  mar  slough;  secondary  pus  infections  take  place,  leading 
to  pyemia  and  septicemia.  There  may  be  severe  pharyngitis 
and  conjunctivitis  followed  by  keratitis  and  blindness. 

{(1)  Hemorrhagic  Po.r. — Between  the  papules  dark  red 
blood  spots  appear  which  involve  the  subcutis.  Nasal 
hemorrhage,  hematuria,  bloody  diarrhea  and  internal  hemor- 
rhage are  not  infrequent.  This  form  (similar  to  "black 
smallpox"  of  man)  is  very  fatal. 

(e)  Gangrenous  l\h\ — Probably  due  to  a  secondary  in- 
fection (necrosis  bacillus?)  is  not  a  special  form  but  may 
attend  otherwise  usual  outbreaks.  Portions  of  the  skin,  and 
even  the  underlying  muscle  in  the  region  of  the  eruption 
become  necrotic  and  slough. 

Complications. — (a)  Dermatitis  may  develop  from  rubbing 
and  scratching  the  vesicles,  especially  in  the  region  of  the  li])s 
and  nostrils. 

(b)  Blindness  from  ulcerative  keratitis  and  later  sui)])ura- 
tiv'e  panoi)hthalniia. 

(c)  Bronchitis  and  catarrhal  pneumonia. 

(d)  Gastro-intestinal  catarrh. 

{(')  Suppurati\e  arthritis  of  the  phalangeal  joints,  shedding 
of  the  claws  and  general  pyemia. 


VARIOLA— POX  343 

Diagnosis, — The  peculiar  character  of  the  exanthema  and 
the  typical  course  usually  make  the  diagnosis  easy.  It  would 
hardly  be  confused  with  scab  or  pustulous  eczema,  as  neither 
of  these  diseases  present  marked  prodromes  and  in  neither 
develop  well-defined,  large  vesicles. 

Course. — The  course  is  acute,  usually  requiring  about  three 
or  four  weeks  to  pass  through  the  different  stages.  Through 
complications,  cold  weather  and  in  run-downi  sheep,  the  course 
may  be  considerably  prolonged.  Sheep-pox  may  remain  in  a 
flock  for  several  months. 

The  mortality  varies  with  the  form  the  disease  assumes. 
^Yhile  in  the  milder  forms  it  may  not  exceed  4  per  cent.,  the 
more  malignant  types  claim  fully  50  per  cent,  as  victims. 

Treatment  and  Prophylaxis. — Usually  a  dietetic  treatment  is 
all  that  is  necessary  (grass,  roots,  gruels).  In  mild  weather 
the  sheep  should  be  turned  out  to  pasture.  Severely  infected 
animals  should  be  slaughtered.  The  medicinal  treatment 
(disinfectants  for  eyes,  salts  for  bowels)  is  expectative  and 
s\-mptomatic.  Sporadic  outbreaks  in  uninfected  districts  are 
best  eradicated  by  slaughter  and  proper  disposition  of  the 
carcasses. 

In  permanently  infected  countries  "ovination"  or  pro- 
tective inoculation  with  sheep-pox  virus  has  been  practised 
with  varying  results.  The  practice  is  dangerous  in  districts 
where  the  disorder  occurs  only  sporadically,  as  the  inoculated 
sheep  can  spread  the  disease. 

Cow-pox  {]\trioIa  ]\iccina). — Definition. — CoAV-pox  is  a  be- 
nign, eruptive  disease  of  the  ox  which  occurs  enzootically  and 
is  characterized  by  a  vesiculopustular  exanthema  occurring 
most  commonly  in  the  udders  of  milch  cows. 

Occurrence. — Cow-pox  is  widely  distributed.  It  is  a  fre- 
quent disease  among  dairy  cows,  to  which  it  is  spread  by 
recently  vaccinated  milkers,  attendants,  etc. 

Etiology. — The  cause  is  evidently  an  ultramicroscopic 
organism  which  passes  tlirougli  coarse  but  not  fine  filters. 

Natural  Infection. — Cow-pox  is  most  commonly  first  intro- 
duced into  a  healthy  herd  by  recently  vaccinated  persons, 
especially  milkers  who  convey  the  x-irus  directly  to  the  udder 
through  the  act  of  milking.     It  is  also  usually-  spread  from 


344    ACUTE  EXANTHEMATOUS  INFECTIOUS   DISEASES 

cow  to  cow  in  the  same  manner.  The  disease  may  also  be 
propagated  by  contaminated  htter,  forage,  food  etc.,  which 
explains  its  oecnrrenc(>  in  heifers,  steers,  and  bnlls. 

Symptoms. — 'llie  period  of  incubation  is  four  to  seven  days. 
The  prodromal  symptoms  are  usually  so  mild  as  to  be  over- 
looked. Occasionally  symptoms  of  general  disturbance 
(fever,  loss  of  appetite,  languor)  precede  the  eruption.  The 
first  local  symptom  noted  is  usually  a  sensitiveness  of  the 
teats  during  milking.  In  two  or  three  days  on  or  at  the  base 
of  the  teat  and  on  the  udder  appear  pea-sized  papules  which 
in  forty-eight  hours  form  \-esicles  the  size  of  a  bean.  The 
\'esicles  contain  a  clear  fluid  and  are  often  pearl-like  in  color. 
On  the  udder  they  are  usually  round  and  on  the  teats  oval  in 
form.  They  are  noted  best  on  the  udder,  near  the  base  of  the 
teat  where  they  are  less  liable  to  be  broken  by  the  milker's 
hands.  The  vesicles  are  usually  siu-rounded  by  a  red  zone. 
^Yhen  intact  they  are  frequently  vunbilicated.  In  eight  to 
fourteen  days  pustules  apj^ear  that  erupt  and  dry  to  form 
crusts  which  slough,  leaving  shallow  pits.  As  a  rule  only  a 
few  vesicles  occur,  usually  not  over  a  dozen  and  occasionally 
only  one  or  two  can  be  foimd.  The  eruption  does  not  take 
place  simultaneously,  several  days  may  elapse  between  the 
formation  of  individual  or  groups  of  vesicles.  Those  which 
form  later  are  generally  smaller  than  the  earlier  ones. 

As  the  vesicles,  especially  those  which  form  on  the  teat,  are 
crushed  during  milking,  secondary  changes  due  to  traumatism 
and  extraneous  infection  are  usual.  From  the  frequent  irri- 
tation of  milking  there  form  ulcers  with  eventually  indurated 
borders  which  heal  only  after  several  Aveeks. 

Parenchymatous  mastitis  is  a  common  complication,  espe- 
cially where  milk-tubes  are  employed  to  draw  oft'  the  milk 
from  the  aft'ected  teats.  In  males  the  disease  is  very  rare  and 
is  said  to  involve  the  scrotal  regions. 

A  generalization  of  the  eruption  is  very  unconnnon.  In 
the  few  cases  recorded  the  vesicles  a])pcared  in  the  inner  side 
of  the  thigh,  on  the  crouj),  body,  chest,  neck  and  muzzle. 

Diagnosis. — The  typical  exanthema,  its  spread  froiu  cow  to 
cow  and  to  the  hands  of  the  milkers,  the  absence  of  general 
symptoms  and  the  benign  course  characterize  the  disease.     In 


FOOT-AND-MOUTH  DISEASE  345 

isolated  cases  where  no  vesicles  can  be  found  and  the  only 
lesions  apparent  a  teat  ulcer,  the  diagnosis  is  impossible. 

Course. — The  disease  usually  lasts  several  weeks  in  a  herd, 
depending  upon  the  number  of  susceptible  animals  and  the 
precautions  taken  to  prevent  its  spread. 

Prognosis. — Good.  The  disease  is  benign  and  does  not 
cause  death.  Economic  loss  is  occasioned  through  the  diminu- 
tion and  polution  of  the  milk,  the  persistency  of  the  teat  ulcers 
and  the  cases  of  mastitis  which  develop  during  the  course  of 
an  outbreak. 

Treatment. — No  internal  treatment  is  necessary.  Washing 
the  teats  and  udder  after  each  milking  with  a  1  per  cent, 
solution  of  sodium  hyposulphite  generally  suffices.  Sterile 
milk-tubes  may  be  used  w^hen  the  teats  are  sore.  The  ulcers 
heal  readily  in  ten  to  fourteen  days  provided  they  are  not 
irritated  during  milking. 

Protective  Inoculation. — Vaccinating  cattle  with  calf  lymph 
(vaccine  points)  intended  for  human  beings  has  been  prac- 
tised in  Europe  with  apparently  good  results 

Horse-pox. — Definition. — Horse-pox  is  a  local  vesiculopus- 
tular  eruption  which  occurs  in  the  region  of  the  fetlocks. 

Etiology. — It  is  probably  cow-pox  transmitted  to  horses  by 
recently  vaccinated  horseshoers. 

Symptoms. — It  is  most  frequent  in  young  horses.  The 
region  of  the  fetlock  becomes  edematous  and  sensitive.  In 
a  few  cases  there  may  be  mild  general  symptoms  (fever) 
which  are  usually  not  noticed.  In  one  or  two  days,  on  the 
posterior  surface  of  the  fetlocks,  there  develop  pea-  to  bean- 
sized  vesicles  which  soon  burst  and  form  crusts.  Occurrence 
on  other  portions  of  the  body  is  rare,  although  cases  are 
recorded  where  the  \'esicles  appeared  on  the  head,  about  the 
mouth  and  nostrils  and  exceptionally  the  buccal  mucous 
membrane  was  invaded.  On  the  limbs  a  temporary  change  in 
the  color  of  the  hair,  which  becomes  lighter,  has  been  noted. 
The  course  is  benign. 

FOOT-AND-MOUTH  DISEASE. 

Definition. — Foot-and-mouth  disease  is  a  very  contagious 
disorder  of  cloven-hoofed  animals,  due  to  an  ultramicroscopic 


340    ACUTE  EXANTHEMATOUS  INFECTIOUS  DISEASES 

organism  and  characterized  by  tlie  formation  of  vesicles  wliicii 
occur  on  the  mucous  membranes  and  skin.  The  mouth,  the 
interdigital  si)ace  and  the  teats  and  udder  are  most  often 
affected. 

Occurrence. — The  disease  has  been  an  occasional  visitor  to 
the  Tnited  States.  In  LSTO  foot-and-mouth  disease  spread 
from  Canada  into  New  England  and  New  York;  in  1884 
there  was  a  limited  outbreak  in  Portland,  IVIaine;  in  1902 
again  in  New  England,  in  the  States  of  Connecticut,  Rhode 
Island,  Massachusetts  and  Vermont;  in  1908  it  was  intro- 
duced through  contaminated  smallpox  vaccine  into  New 
York,  Pennsylvania,  Michigan  and  Maryland;  in  1914  the 
most  wide-spread  outbreak  in  the  history  of  the  country 
occurred.  \Vithin  tlu-ee  months  the  disease  spread  from  the 
Chicago  stockyards  to  Michigan  and  Ohio  and  ultimately 
infected  twenty-one  States  and  the  District  of  Columbia. 
The  origin  of  this  outbreak  is  in  dispute,  but  it  prob- 
ably came  from  contaminated  anti-hog  cholera  serum.  In 
Europe,  Asia  and  Africa  and  in  South  America  foot-and- 
mouth  disease  is  prevalent.  While  not  an  especially  fatal 
disease,  it  occasions  enormous  losses  due  to  its  rapid  spread, 
the  damage  it  causes  the  milk  industry,  the  losses  entailed 
through  (piarantine  and  the  sequehe  (loss  of  claws,  mastitis, 
etc.)  which  follow  in  the  wake  of  an  outbreak.  The  damage 
done  the  cattle  industry  amounts  to  an  average  of  $20  per 
head  for  each  animal  aft'ected. 

Etiology. — The  cause  is  e\'idently  an  ultramicroscopic  virus 
which  passes  through  coarse  but  not  the  finest  bacterial  filters. 
The  virus  is  present  in  the  vesicles  and  is  found  in  the  blood 
only  in  the  early  part  of  the  fever  stage.  The  saliva,  tears, 
milk  and  nasal  discharge  are  infectious  from  contamination 
with  the  contents  of  the  vesicles.  As  the  disease  progresses 
the  virulency  of  the  virus  decreases. 

Natural  Infection. — The  virus  of  foot-and-mouth  disease  is 
taken  up  ])y  the  digestive  tract  with  food,  water,  bedding, 
litter,  etc.  which  have  become  contaminated  ])rincipally  by 
the  saliva  of  affected  animals.  Such  intermediary  agents  as 
stable  utensils,  mangers,  watering  troughs,  clothing  and  the 
hands  of  attendants,  etc.,  may  also  harbor  the  virus.    Railway 


FOOT-AXD-MOVTH  DISEASE  347 

cars,  stockyards,  cattle  pens,  manure,  hides,  wool,  milk, 
veterinarians,  butchers,  cattle  dealers,  herders,  etc.,  are  also 
carriers  of  the  contagion.  Hay,  straw,  feed  and  the  like 
imported  from  infected  districts  often  spread  the  disease.  In 
1908,  as  noted,  foot-and-mouth  disease  was  introduced  into 
the  United  States  by  some  calves  used  for  the  propagation  of 
vaccine  virus,  which  had  been  inoculated  T;\-ith  contaminated 
lymph  imported  from  Japan.  It  is  very  probable  that  re- 
covered animals  ("germ  carriers")  may  harbor  the  virus  for 
an  indefinite  period,  which  accounts  for  sporadic  outbreaks  of 
the  disease  in  uninfected  districts. 

^Vhile  cattle  are  most  predisposed,  the  disorder  also  attacks 
sheep,  swine,  goats  and  buffalo.  It  is  rare  in  horses,  dogs  and 
cats. 

One  attack  produces  immunity  for  only  a  short  period 
(usually  not  over  one  year).  In  certain  individuals  no 
immunity  is  conferred,  the  animal  suffering  within  a  few 
months  repeated  attacks.  Calves  born  of  cows  attacked  in 
advanced  pregnancy  are  sometimes  (not  always)  highly  re- 
sistant to  either  natural  infection  or  artificial  inoculation. 

Symptoms. — The  period  of  incubation  is  two  to  seven  days, 
although  it  may  be  longer. 

The  prodromal  s\Tnptoms  are  those  of  fever,  the  tempera- 
ture reaching  106°  T.,  lasting  one  or  two  days,  and  falling  to 
normal  as  soon  as  the  vesicles  appear.  Unless  complications 
arise  from  secondary  infection,  no  fmther  rise  in  temperature 
occurs  during  the  course  of  the  disease. 

^yith  the  fever  there  is  a  period  of  loss  of  appetite,  sup- 
pressed rimiination  and  languor.  The  mouths  of  the  patients 
become  sore,  causing  them  to  masticate  slowly  and  in  an 
interrupted  fashion.  The  mouth  is  usually  held  closed,  saliva 
hanging  from  the  commissures  in  long  strands.  When  opened 
a  peculiar  smacking  sound  is  made.  Where  a  number  of 
affected  cattle  are  housed  together  the  noise  produced  is 
marked. 

On  examining  the  mouth  one  or  two  days  after  the  begin- 
ning of  the  attack,  the  mucous  membrane,  especially  of  the 
lips,  gums,  dental  pad  and  tongue,  shows  a  vesicular  eruption, 
the  individual  vesicles  varying  in  size  from  a  pea  to  a  walnut. 


348    ACUTE  EX  ANTHEM  ATOim  INFECTIOUS  DISEASES 

The  large  l^listers  rupture  in  about  one  day,  leaving  behind  an 
excoriated  surface  of  a  brown-red  color,  which  is  often  covered 
with  a  gray  deposit.  The  smaller  vesicles  ])ersist  for  two  or 
three  days.  On  the  back  of  the  tongue  one  to  three  walnut- 
sized  vesicles  are  often  noted.  As  the  organ  is  extremely  sore 
and  therefore  little  moved,  the  blisters  remain  intact  for  two 
or  three  da\'s.  The  contents  of  the  vesicles  are  clear  or 
yellowish.  Where  they  erupt  a  very  sensitive,  highly  red- 
dened, shallow  erosion  is  left  which  becomes  covered  with  new 
eijithelium  in  two  or  three  days.  When  healing  is  well  under 
way  the  eroded  area  appears  as  a  brown-yellow  spot  which 
eventually  disappears.  As  soon  as  the  erosions  are  sufficiently 
covered  with  epithelium  the  emaciated  patient  begins  to  eat. 

In  some  cases  the  muzzle  (snout  of  swine),  base  of  the 
horns  (very  rare),  nasal  mucous  membrane,  conjunctiva, 
pharynx  (dysphagia,  cough,  regurgitation)  and  even  the 
cornea  are  similarly  involved. 

The  foot  lesions  induce  lameness  with  knuckling  of  the 
fetlock  of  the  limb  attacked.  If  two  or  more  feet  are  af- 
fected the  patient  lies  down  most  of  the  time  and  is  made  to 
arise  with  difficulty.  The  coronet  is  hot  and  swollen,  espe- 
cially in  front  and  between  the  bulbs  of  the  heels.  In  some 
cases  the  swelling  extends  up  the  leg  to  the  middle  of  the 
canon.  On  the  second  or  third  day  of  the  attack  pea-  to 
bean-sized  vesicles  appear  in  the  swollen  area.  The  vesicles 
ruj)ture  very  early  and  lea^'e  behind  sores  co^'ered  with  a 
tough,  brown  scab.  Healing  usually  requires  one  or  two 
weeks.  In  severe  cases,  from  secondary  infection,  shedding 
of  the  claws  results. 

In  swine  and  sheep  only  the  feet  ni;iy  be  attacked,  no 
mouth  lesions  being  ap])arent. 

In  cows  the  skin  of  the  teats  and  udder  is  often  affected, 
most  often  the  former.  The  vesicles  are  from  the  size  of  a 
pea  to  a  hazel  nut  and  are  generally  ru])tured  during  milking. 
The  teats  are  swollen,  sometimes  phlegmonous  (secondary  in- 
fection) and  extremely -sensitive.  Later  the  sores  become 
covered  with  scabs  and  heal. 

Catarrhal  mastitis  frequently  attends  the  exanthema,  lead- 
ing to  changes  in  the  milk,  which  becomes  colostral,  has  an 


FOOT-AND-MOUTH  DISEASE  349 

acid  reaction,  coagulates  readily  and  is  difficult  to  make  into 
butter  or  cheese. 

Complications  and  Seqnelce. — The  most  serious  complica- 
tions are  phlegmons  of  the  digits  which  lead  to  suppurative 
inflammation  of  the  tendon  sheaths,  tendons,  joints  and 
horn  matrix,  inducing  severe  general  disturbance  (fever,  high 
pulse) ,  inability  to  stand,  decubital  gangrene,  septicemia  and 
death  in  one  or  two  weeks. 

Septic  infection  of  the  udder  (parenchymatous  mastitis) 
is  not  an  uncommon  complication  which  may  cause  the  loss  of 
a  cjuarter  or  a  half  of  the  organ. 

Gastro-enteritis  is  a  fatal  complication  in  calves,  leading  to 
death  in  two  or  three  days. 

Diagnosis. — In  typical  cases,  during  the  vesicular  stage 
of  the  eruption,  the  diagnosis  is  not  difficult.  The  presence  of 
vesicles,  the  foot  lesions,  the  rapid  spread  of  the  contagion 
and  the  ease  with  which  it  may  be  transmitted  artificially 
characterize  the  disorder. 

During  the  early  stages  (before  the  eruption)  and  at  the 
end  of  a  sporadic  outbreak  (vesicles  healed  or  only  secondary 
changes  present)  the  diagnosis  can  be  extremely  difficult. 

Foot-and-mouth  disease  may  be  confused  with  various 
forms  of  stomatitis  in  cattle,  none  of  which  are  contagious 
but  some  of  which  are  attended  with  ^'esicle  formation.  The 
most  important  are  the  following : 

(a)  Traumatic  stomatitis  ("  tooth  cuts")  presents  lesions  on 
the  bars,  lips  and  dental  pad.  There  is  no  vesicle  formation 
and  the  wounds  have  sharp  borders  and  are  deep. 

(6)  Mycotic  stomatitis  of  cattle,  a  non-contagious  foot-and- 
mouth  affection  wide-spread  in  the  United  States.  Vesicles 
rarely  appear  and  are  never  well  developed.  The  mouth 
lesions  are  more  ulcerous  in  character  than  in  foot-and-mouth 
disease  and  are  more  apt  to  involve  the  deeper  structures. 
There  is  more  swelling  of  the  limbs  but  no  vesicles  occur  at  the 
coronets.  A  peculiar  reddish-brown  coloration  of  the  muzzle, 
udder  and  teats  is  considered  characteristic  by  some  authori- 
ties. The  disease  cannot  be  transmitted  by  inoculation  and 
does  not  affect  sheep  or  swine.  Often  only  a  few  animals  in 
a  herd  are  attacked. 


350    ACUTE  EXANTHEMATOUS  INFECTIOUS  DISEASES 

(c)^ Ergotism. — Ergotism  produces  gangrene  of  tlie  distal 
j)()rtions  of  tiie  extremities  (feet,  ears,  tail),  the  necrotic  parts 
sloughing.  Blisters  are  not  common  and  when  present  not 
well  marked.  This  poisoning  is  not  contagious  and  cannot  he 
transmitted  artificially  from  animal  to  animal.  It  occurs 
only  among  cattle  which  have  eaten  ergot-of-rye. 

(d)  Necrotic  Stomatitis. — Nearlj^  always  seen  in  calves 
("calf  diphtheria")  and  pigs  ("sore  mouth").  There  is  no 
\'esicle  formation  but  a  necrosis  of  the  nnicous  membrane, 
yellow-gray  patches  de\'eloping  in  the  mouth  (cheeks, 
tongue) . 

(e)  Foot-rot  of  Sheep. — A  contagious  disease  of  the  inter- 
digital  space  which  may  later  induce  suppurative  pododerma- 
titis,  tendovaginitis,  open  joint,  etc.  There  are  no  ^'esicles 
and  the  disease  spreads  slowly  through  a  Hock. 

(/)  Foul-in-the-feet  of  cattle  due  to  filthy  stables  and  barn- 
yards does  not  affect  the  mouth;  there  are  no  vesicles  and  no 
contagion.  A  malignant  type  of  foul-in-the-fcct  due  to  the 
necrosis  bacillus  and  a})i)cariiig  in  cows  :^oon  after  parturition 
or  in  advanced  pregnancy,  assumes  the  form  of  a  necrosis  of  the 
interdigital  space  which  may  involve  the  deeper  structures 
(matrix,  tendon  sheaths,  tendons,  joints).  It  is  attended  by 
fever  when  secondary  infection  is  ])rcsent.  The  mouth  is  not 
invoh'ed. 

The  indications  which  point  to  foot-and-mouth  disease  in 
a  recently  recovered  animal  are:  Pytalism  (usually  jirofuse); 
yellow  cicatrices  or  areas  on  gums  and  dental  pad;  small  red 
spots  and  erosions  in  the  gums  and  borders  of  the  muzzle. 
These  traces  are  said  to  persist  for  several  weeks. 

Course. — In  most  outbreaks  the  course  is  benign.  ln(li\i- 
dual  vesicles  usually  heal  in  fi\'e  or  six  days,  but  as  they  do  not 
all  erupt  at  the  same  time,  the  dvu'ation  is  often  extended  two 
or  three  weeks.  The  mouth  lesions  heal  more  rapidly  than 
do  those  of  the  feet.  As  all  animals  are  not  infected  simul- 
taneously, an  outbreak  will  last  in  a  given  barn  one  or  two 
months. 

In  calves  (under  two  months)  the  course  is  more  rai)id  and 
fatal  (toxemia,  septicemia,  pyemia,  gangrenous  pneumonia, 
heart  muscle  degeneration)  leading  to  death  in  three  or  four 
days. 


FOOT-AX D-MOUTH  DISEASE  351 

From  resulting  foot  troubles  (panaritium,  suppiu'ative 
tendovaginitis,  open  joint,  interdigital  ulceration),  loss  of 
flesh  and  milk  (udder  complications)  the  course  is  not  only 
prolonged  but  the  patient's  economic  value  may  become 
permanently  reduced. 

Prognosis. — The  disease  is  benign  except  in  very  young 
animals,  when  it  assumes  a  malignant  form  and  when  com- 
plications due  to  secondary  infection  occur  (loss  of  claws, 
decubitus,  septicemia,  etc.).  It  is  rare  for  the  mortality  to 
exceed  1  per  cent,  in  the  benign  type.  It  may  exceed  50 
per  cent.,  however,  in  the  rarer,  malignant  type. 

Treatment. — In  countries  like  the  United  States,  which  are 
not  permanently  infected,  no  treatment  should  be  tolerated. 
The  extreme  contagiousness  of  the  disease  and  its.  rapid 
spread  justify  the  most  radical  methods  of  eradication. 
These  consist  in  the  immediate  slaughter  of  all  affected  ani- 
mals, the  proper  disposition  of  the  carcasses  (deep  biuial, 
cremation)  and  a  thorough  disinfection  of  the  premises. 

In  countries  where  foot-and-mouth  disease  is  wide-spread 
and  radical  methods  of  stamping  it  out  cannot  be  employed, 
the  following  indications  in  the  way  of  therapy  are  followed: 

The  cattle  should  be  fed  only  soft,  sloppy  food  (bran 
mashes,  root  pulp,  grass)  and  allowed  plenty  of  water.  The 
mouths  may  be  irrigated  twice  daily  with  some  non-toxic 
disinfectant  (pyoctanin  1  to  1000).  The  stable  floors  should 
be  kept  clean  and  dry  and  the  feet  treated  with  disinfectants 
(may  be  stood  in  a  shallow  bath  of  2  per  cent,  creolin  solution). 
To  the  teats  and  udder  boroglycerin,  camphor  ointment,  etc., 
are  useful.  Mastitis  should  be  treated  as  such.  Complica- 
tions (shedding  of  claws,  tendovaginitis,  etc.)  are  handled 
according  to  surgical  principles. 

The  milk  should  not  be  used  diuing  the  outbreak.  In  a 
raw  state  it  is  fatal  to  sucklings  and  when  sterilized  it  is  not 
wholesome. 

General  symptoms  (heart  weakness,  high  fever)  are  met 
as  they  occur  (oil  of  camphor  subcutaneously,  digitalis,  al- 
cohol, acetanilid). 

As  foot-and-mouth  disease  is  a  self-limiting  disease  which 
usually  takes  a  typical  coiu-se,  in  uncomplicated  cases  not 
much  medicinal  treatment  is  needed. 


352    ACUTE  EXANTHEMATOUS  INFECTIOUS  DISEASES 

Formerly  it  was  a  common  practice,  when  foot-and-mouth 
disease  appeared  on  the  premises,  to  inoculate  all  cattle  still 
healthy  by  rubbing  saliva  from  an  infected  animal  into  the 
mucous  membrane  of  the  mouth.  This  method  infected  the 
whole  herd  simultaneously  and  lessened  the  virulence  of  the 
attack.  It  is  seldom  permitted  nowadays,  although  it  has 
much  to  recommend  it. 

Protective  and  Therapeutic  Inoculations. — Various  methods 
(for  which  see  larger  works)  of  preventive  vaccination  have 
been  tried  with  as  yet  indifferent  success. 

CONTAGIOUS  STOMATITIS  OF  THE  HORSE. 

Definition. — Contagious  pustulous  stomatitis  is  an  acute, 
benign,  infectious  disease  of  the  horse  characterized  by  its 
marked  contagiousness  and  the  appearance  of  pustules  in  the 
mucous  membrane  of  the  mouth.  Sometimes  the  nasal 
mucosa  and  the  skin  of  the  lips  are  involved. 

Occurrence. — The  disease  is  widely  distributed,  appearing 
enzootically  chiefly  among  colts  or  young  horses  herded 
together  in  barns  or  on  pastures.  While  the  disease  is  usually 
benign,  the  patients  lose  flesh  and  older  horses  are  often  unable 
to  work  during  the  attack.  Occasionally  foreign-body  pneu- 
monia may  complicate  the  disease  (pneumonia  medicantaria 
from  needless  drenching). 

Etiology. — The  cause  is  unknown.  The  virus  seems  to  be 
contained  in  the  nodules  and  y)ustules;  the  saliva  is  therefore 
virulent.  The  disease  is  readily  transmitted  artificially.  A 
spread  to  other  animals  (sheep,  cattle,  swine)  and  evvn  man  is 
recorded.  This  is  rare,  however,  as  the  disease  is  seen  ordi- 
narily only  in  the  horse. 

Natural  Infection. — Contagious  pustulous  stomatitis  is 
spread  by  the  saliva  of  the  sick  which  contaminates  the  food 
and  water.  Transmission  through  i)olluted  stable  litter, 
utensils,  sponges,  hands  of  attendants,  etc.,  also  occurs.  The 
disease  does  not  assume  an  epizootic  form  probably  because 
the  virulency  of  the  virus  rapidly  attenuates  in  passing  from 
animal  to  animal.  Usually  all  horses  exposed  do  not  become 
infected. 


COXTAGIOUS  STOMATITIS  OF   THE  HORSE        353 

The  disease  is  generally  introduced  into  a  stable  or  pasture 
))>■  an  infected  animal. 

Symptoms. — The  period  of  incubation  is  tlu-ee  to  five  days. 
The  first  symptoms  noted  are  usually  impairment  of  appetite 
and  ptyalism.  The  patient  holds  the  mouth  shut;  if  opened 
a  quantity  of  saliva  spills  out.  The  saliva  is  very  viscid  and 
hangs  in  long  tlireads  from  the  mouth.  The  lips  and  cheeks 
are  somewhat  swollen  and  tender.  On  examination  of  the 
mouth,  which  the  patient  often  resists,  the  mucosa  appears 
congested  and  streaked  with  red.  On  the  mucous  sm-face  of 
the  lips,  gums,  the  hard  palate  and  particularly  beneath  the 
tongue  about  the  frenum  appear  firm  red  papules  the  size  of 
a  pea.  The  papules  do  not  all  erupt  at  the  same  time,  but 
successively,  a  fresh  crop  appearing  after  tw^o  or  tliree  days. 
From  the  papules  vesicles  form.  The  smaller  vesicles  break 
and  heal  while  the  larger  ones  tm-n  to  pustules  which  perfo- 
rate, lea\-ing  behind  small  round  ulcers.  Sometimes  two  or 
more  ulcers  coalesce  forming  large  irregidar  areas  of  ulcera- 
tion. The  ulcers  usually  heal  in  a  few  days,  lea\'ing  behind 
a  white  scar. 

In  some  cases  the  pustular  eruption  may  involve  the  lower 
part  of  the  nasal  mucosa  especially  of  the  wdngs  of  the  nostrils. 
Xasal  discharge  may  be  present  which  dries  and  adheres  as 
brow^l  crusts  to  the  borders  of  the  al*.  In  rare  instances  the 
lacrimonasal  canal  is  invaded,  the  infection  spreading  through 
it  to  the  conjunctiva. 

Sometimes  the  external  skin  is  involved.  There  appear  on 
the  lips,  nostrils  and  cheeks  papules,  vesicles  and  pustules  like 
those  observed  on  mucous  membranes.  Cases  are  recorded 
where  the  eruption  appeared  on  other  parts  of  the  body 
(breast,  shoulder,  thigh). 

The  l\Tnph  vessels  and  glands  adjacent  to  the  eruption  fre- 
quently swell,  the  vessels  forming  cord-like  strands.  There  is 
no  tendency,  however,  for  abscesses  to  form  along  their  course 
as  in  strangles.     The  submaxillary  hmph  glands  are  swollen. 

Diagnosis. — The  diagnosis  is  usually  not  difficult.     If  the 

case  is  at  all  t^-pical,  it  is  exceedingly  easy.     The  contagious 

character  of  the  disease  and  the  formation  of  papules  ending 

in  pustules  and  ulcers  is  indicative.     In  vesicular  stomatitis, 

23 


354    ACUTE  EXANTHEMATOUS  INFECTIOUS   DISEASES 

which  develops  only  in  the  mucous  membrane  of  the  lower 
jaw  especially  in  the  rcf^ion  of  the  frenum  of  the  tongue, 
vesicles  (clear  fluid  contents)  appear  but  never  papules. 
Small  abscesses  and  ulcers  which  occur  in  the  mucous  mem- 
brane of  the  mouth  as  the  result  of  traumatism  or  caustics 
do  not  form  pustules,  the  ulcers  are  usually  deej^er  seated,  and 
there  is  no  evidence  of  contagiousness.  In  contagious  acne 
the  mucous  membranes  are  not  involved,  although  large 
pustules  appear  upon  the  skin  in  the  region  of  the  harness 
rests.  It  could  be  confused  only  with  those  rare  cases  of 
contagious  pustulous  stomatitis  Avhich  do  not  involve  the 
mucous  membranes.  Coital  exanthema  affects  the  genital 
organs.  Horse-pox  is  confined  to  the  region  of  the  fetlocks. 
If  the  nasal  mucosa  is  invoh'cd  contagious  pustulous  stoma- 
titis might  be  confused  with  glanders.  Glanders,  however, 
does  not  affect  the  buccal  cavity.  The  ready  healing  of  the 
ulcers  and  the  rapid  spread  to  other  horses  are  not  noted  in 
glanders. 

Course. — The  disease  usually  lasts  about  two  weeks  and 
ends  in  complete  recovery.  It  requires  three  to  six  days  for 
the  pustules  to  develop,  they  remain  about  four  or  five  days 
and  form  ulcers  which  heal  in  about  the  same  time.  Severe 
cases  may  take  a  more  protracted  course  in  that  one  eruption 
follows  another  in  succession.  Fatal  cases  are  rare.  They 
result  usually  from  secondary  infection  with  pus  organisms  or 
the  necrosis  bacillus  or  in  that  pharyngitis  develops  from  the 
specific  process  extending  back  to  the  j)harynx,  causing  dys- 
])hiigia  and  occasionally  foreign-body  pneumonia. 

Treatment. — Internal  medication  is  rarely  indicated.  The 
patient  should  be  fed  soft  food  such  as  grass,  gruels,  bran 
mashes,  etc.,  and  allowed  constant  access  to  fresh  water.  The 
mouth  may  be  syringed  out  two  or  three  times  daily  with  a 
2  ])er  cent,  lysol  solution.  Skin  ulcers  may  be  treated  with 
compound  alum  powder. 

Prophylaxis. — If  only  a  few  horses  are  aflfected  they  should 
be  isolated  and  given  separate  attendants.  If,  howe\'er,  the 
disease  is  generally  distributed  and  further  sj>read  inevitable, 
to  shorten  the  course  of  the  outbreak  it  is  recommendable  to 
inoculate  the  still  healthy  animals.     This  is  easilj'  performed 


COITAL  EXANTHEMA  355 

by  taking  a  clean  towel,  passing  it  tlirough  the  mouth  of  an 
infected  animal,  and  then  through  the  mouth  of  those  animals 
which  have  not  yet  taken  the  disease.  A  thorough  disin- 
fection of  the  premises  should  follow. 

COITAL  EXANTHEMA. 
Eruptive  Venereal  Diseases.    Genital  Horse-pox. 

Definition. — Coital  exanthema  is  a  benign  acute  contagious 
disease  of  the  external  genital  organs  of  cattle,  horses,  sheep 
and  swine.  It  is  characterized  by  a  vesicular  eruption  which 
is  transmitted  from  animal  to  animal  by  the  act  of  coitus. 

Occurrence. — The  disease  is  very  common  in  horses  and 
cattle,  outbreaks  occurring  during  the  spring  and  summer. 
It  is  sometimes  confused  with  variola  with  which  it  has  prob- 
ably no  connection.  While  the  disease  is  benign  it  interferes 
with  breeding,  lactation  in  cows,  and  by  affecting  a  number  of 
animals  in  a  district,  attains  economic  importance.  It  is 
quite  common  in  the  United  States. 

Etiology. — ^The  cause  of  the  disease  is  not  yet  known.  The 
virus  seems  to  be  contained  in  the  lymph  of  the  vesicle  or  the 
pus  of  the  pustule  or  ulcer  from  which  it  may  be  transmitted 
by  artificial  inoculation. 

Natural  Infection. — Coital  exanthema  is  nearly  always  trans- 
mitted by  coition  whereby  the  male  animal  infects  the  female 
and  vice  versa.  The  disease  is  spread  usually  by  an  infected 
stallion  or  bull.  It  is  claimed  that  the  male  may  transmit 
the  disease  without  himself  becoming  infected  in  that  the 
infectious  secretions  from  a  diseased  female  adhere  to  the 
penis  and  are  lodged  in  the  vulva  or  vagina  of  the  female 
served  by  him  soon  after.  This  natm-ally  would  only  apply 
where  the  service  was  performed  within  an  hour  or  two 
following  copulation  with  an  infected  female. 

The  disease  once  in  a  while  occiu-s  in  females  in  advanced 
pregnancy,  also  in  animals  which  have  not  been  bred.  This 
would  indicate  that  occasionally  intermediary  agents  such  as 
contaminated  stable  litter,  utensils,  sponges,  etc.,  may  carry 
infection, 


356    ACUTE  EXANTHEMATOUS  INFECTIOUS   DISEASES 

Cattle  seem  to  be  more  susceptible  than  horses;  the  disease 
is  less  commonly  seen  in  sheep,  goats,  and  swine.  One  attack 
produces  a  transient  immunity,  although  cases  are  recorded 
where  one  and  the  same  animal  has  been  attacked  repeatedly. 

Symptoms. — The  period  of  incubation  is  usually  from  two  to 
fi\e  days.  A  minimum  period  of  twenty-four  hours  and  a 
maximum  period  of  nearly  two  weeks  have  been  recorded. 
The  first  symptoms  in  females  are  inflammation  of  the 
mucous  membrane  of  the  vulva  and  vagina  in  which  appear 
small  red  papules  which  in  two  or  three  days  form  red,  pea- 
sized  \'esicles  containing  a  clear  yellow  fluid.  The  lesions 
are  commonly  found  in  the  upper  commissure  of  the  vulva 
and  in  the  neighborhood  of  the  clitoris  and  the  mucous  surface 
of  the  lips  of  the  vulva. 

Similar  eruptions  may  invade  the  skin  around  the  vulva, 
anus,  and  the  perineum.  In  a  short  time,  from  secondary 
infection,  the  vesicles  become  pustules,  which  erupt,  leaving 
behind  shallow  ulcers  which  heal  readily  by  granulation.  In 
some  cases,  however,  the  ulcers  are  deeper,  and  when  they 
heal  there  is  left  behind  a  white  or  yellow  scar  which  in  time 
tends  to  disappear.  In  some  instances  after  the  eruption  of 
the  pustule  tough,  yellow  crusts  nearly  a  quarter  of  an  inch 
thick  remain.  When  these  crusts  are  remoN'ed  or  drop  off, 
white  areas  remain  which  are  usually  small  and  circular,  but 
by  confluence  larger  and  irregular  in  form. 

The  lips  of  the  vulva  are  edematously  swollen  as  may  be 
the  surrounding  parts.  In  mares  repeated  blinking  of  the 
vulva  is  noted.  There  is  a  vaginal  discharge  of  a  mucopuru- 
lent character  which  soils  the  tail  and  buttocks. 

In  male  animals  a  similar  eruption  appears  upon  the  penis, 
prepuce,  and  sheath.  The  jxMiis  itself  is  swollen,  and  from 
the  urethra  flows  a  muco])urulent  discharge.  The  above- 
described  depigmented  areas  noted  in  female  animals  are  also 
seen  on  the  penis  in  males.  Urination  is  frequent  and  accom- 
panied by  considerable  straining,  the  patient  often  switching 
its  tail,  arching  the  back  and  kicking  against  its  abdomen. 
In  males,  esi)eciall>'  stallions,  the  penis  is  often  erected  and  a 
yellowish  nuicopurulent  discharge  flows  from  the  urethra. 

Ordinarily  the  general  condition  of  the  animal  is  not  im- 


COITAL  EXANTHEMA  357 

paired.  The  appetite  is  usually  retained  and  there  is  no  loss 
of  flesh.  On  the  other  hand,  where  the  eruption  has  been 
extensive  and  associated  with  nuieh  })ruritus,  there  may  be 
restlessness,  frequent  straining  as  if  to  urinate,  the  patient 
seeming  much  disturbed. 

Pruritus,  however,  is  not  a  constant  s\Tnptom. 

The  usual  benign  course  of  the  disease  may  be  perverted 
by  secondary  infection  or  through  the  patient  rubbing  the 
ulcerous  surfaces.  Thus  in  individual  cases  general  pyemia 
or  septicemia  may  follow. 

Diagnosis. — The  diagnosis  is  usually  not  difficult.  The 
appearance  of  the  vesicles  and  the  ready  spread  by  coition 
usually  suffice  for  a  diagnosis.  If,  however,  no  vesicles  can 
be  found,  the  condition  might  be  confused  with  ulceration 
due  to  other  causes.  In  this  regard  the  rapid  healing  of  the 
ulcer  is  suggestive.  In  granular  vaginitis  of  cattle,  red-gray 
nodules  appear  which  give  to  the  aft'ected  parts  of  the  vagina 
a  granular  appearance.  Vesicles  are  very  rarely  noted.  The 
disease  could  hardly  be  confused  with  dourine,  as  it  is  much 
more  contagious,  its  course  more  rapid  and  termination 
benign. 

Course. — ^The  course  of  the  disease  is  usually  brief  and  mild. 
Spontaneous  recovery  occurs  in  the  majority  of  cases  in  two 
to  four  weeks.  In  severe  cases  or  where  proper  treatment  has 
not  been  applied  the  secondary  lesions  developing  from  trau- 
matism or  infection  may  take  months  to  cure.  In  rare  in- 
stances chronic  vaginal  catarrh,  metritis,  cystitis  and  the 
like  may  follow.  In  bulls  abscess  of  the  penis  may  perma- 
nently deform  the  organ  or  so  weaken  it  that  the  animal  is 
incapable  of  performing  the  coital  act. 

Treatment. — In  mild  cases  no  special  treatment  is  necessary, 
although  it  is  advisable  to  wash  off  the  affected  parts  of  the 
genital  organs  with  disinfectants  (phenol  Bj,  tannin  5j, 
glycerin  5vj,  water  one  gallon).  Before  applying  disinfec- 
tants to  the  penis  it  should  be  washed  thoroughly  with  soap 
and  water,  rinsed  and  dried.  Obstinate  ulcers  which  remain 
behind  may  be  treated  with  nitrate  of  silver  or  copper  sul- 
phate. Some  recommend  flushing  out  the  urethra  with  mild 
antiseptics.  This  is,  however,  rarely  necessary.  That  an 
infected  animal  should  not  be  bred  is  obvious. 


CHAPTER   III. 

ACUTE   INFECTIOUS   DISEASES  LOCALIZED   IN 
CERTAIN  ORGANS. 

STRANGLES.     CORYZA  CONTAGIOSA  EQUORUM. 

Definition. — Strangles  is  an  acute  contagio-infectious  dis- 
ease of  horses,  asses  and  mules,  due  to  a  specific  streptococcus, 
which  leads  to  catarrh  of  the  upper  air  passages  and  abscess 
formation  in  hTuph  glands. 

Occurrence. — Strangles  is  a  disease  of  colthood  and  is 
therefore  most  prevalent  in  breeding  districts.  Adult  or 
aged  horses  are  more  rarely  attacked.  The  disease  is  most 
common  in  colts  from  six  months  to  five  years  of  age,  although 
cases  in  patients  under  two  months  are  not  rare.  The  dis- 
ease is  wide-spread,  but  Ireland  and  the  Argentine  Republic 
are  said  to  be  free  from  it.  Generally  speaking,  strangles  is 
a  benign  disease,  but  by  checking  the  growth  and  sometimes 
causing  the  death  of  colts,  it  attains  economic  significance. 
Furthermore,  some  outbreaks  are  malignant  in  character 
and  lead  either  to  considerable  losses  from  death  (internal 
abscesses)  or  permanent  injury  through  sequehe  (roaring, 
pharyngeal  paralysis). 

Etiology. — The  Streptococcus  equi  of  Shiitz,  found  in  tlie 
lym])h  glands  and  nasal  discharge  of  affected  animals. 

Natural  Infection. — The  streptococcus  probably  enters  the 
body  through  the  intact  nasal  mucous  membrane,  although 
other  mucous  surfaces  (throat,  bowel,  vagina)  may  form  i)orts 
of  entry.  Nasal  discharge  and  pus  from  lymph-gland  ab- 
scesses or  more  rarely  skin  lesions  are  taken  in  with  the  food 
and  water,  reaching  the  upper  air  passages. 

In  breeding  establishments  strangles  is  usually  introduced 
by  a  horse  which  has  not  yet  fully  recovered  from  the  disease. 


STRANGLES— CORYZA  CONTAGIOSA  EQUORUM      359 

By  direct  contact  with  such  an  animal  or  one  showing  pro- 
nounced symptoms  of  the  disease  susceptible  horses  are  readilj'^ 
infected.  In  a  barn  where  strangles  exists  the  air  will  be 
more  or  less  impregnated  with  globlets  of  discharge  containing 
streptococci,  especially  if  the  ventilation  is  bad.  Mangers, 
water  buckets,  troughs,  stall  partitions  and  floors  contami- 
nated with  nasal  or  abscess  discharge,  may  under  favorable 
conditions  retain  the  infection  for  several  months.  There- 
fore, horses  placed  in  stables  where  the  disease  has  existed  or 
if  they  are  permitted  to  eat  or  drink  out  of  infected  buckets, 
watering  troughs,  etc.,  may  ingest  the  streptococci  of  the 
disease.  Livery  and  dealers'  stables  are  thus  more  or  less 
permanent  sources  of  infection,  each  year  outbreaks  occurring 
in  them. 

Colts  may  infect  their  dams  by  nursing;  stallions,  mares 
during  the  act  of  coitus.  Intra-uterine  infection  may  also 
occur. 

Some  outbreaks  which  are  not  traceable  to  any  recogniz- 
able source  may  possibly  be  due  to  a  saprophytic  life  which 
the  streptococcus  is  thought  to  assume. 

One  attack  of  strangles  usually  affords  life-long  immunity. 
There  are,  however,  many  exceptions,  individual  animals 
suffering  two  or  more  attacks  of  the  disease. 

Any  factor  (refrigeration,  overwork,  poor  food  and  care, 
etc.)  which  reduces  the  resistance  of  the  horse  predisposes  it 
to  the  disease. 

Necropsy. — ^The  postmortem  lesions  are  those  of  pj^emia 
with  abscesses  in  lymph  glands  (mediastinal,  bronchial,  mes- 
enteric) or  in  any  of  the  parenchymatous  organs.  Broncho- 
pneumonia or  suppurative  pneumonia  with  lung  abscess  alone 
or  combined  with  pleuritis  and  pericarditis  is  commonly 
noted.  In  the  abdominal  cavity  the  mesenteric  lymph  glands 
are  found  involved.  In  some  instances  a  spontaneous  rupture 
of  the  abscess  has  occurred  leading  to  a  diffuse  purulent 
peritonitis.  In  others  a  more  chronic  condition  is  noted 
(adhesive  peritonitis)  with  adherent  loops  of  bowel.  Where 
there  has  been  general  metastasis,  multiple  abscesses  may 
form  in  any  organ  of  the  body  (brain,  muscle,  thymus, 
heart,  etc.). 


360       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

Symptoms. — From  a  clinical  standpoint  it  is  useful  to 
classify  the  cases  in  two  types:  (a)  regular  strangles,  and  (/>) 
irregular  ("bastard")  strangles. 

Cases  of  regular  strangles  are  those  which  take  a  relatively 
rapid  and  benign  course,  while  those  spoken  of  as  irregular 
have  a  protracted  course  or  suffer  threatening  complications 
or  sequela".  The  period  of  incubation  is  from  one  to  eight 
days,  usually  three  or  four  days.  The  symptoms  of  the  first 
type  are:  Cough  from  an  affection  of  the  larynx  or  bronchi. 
The  cough  may  persist  a  week  or  two  after  the  other  symp- 
toms have  subsided. 

Nasal  Discharge. — At  first  the  discharge  is  watery  but  soon 
becomes  mucopurulent.  It  is  usually  viscid  and  copious.  If 
dysphagia  is  present,  food,  water  or  saliva  are  mixed  with 
it.  The  discharge  usually  lasts  eight  to  fourteen  days, 
gradually  becoming  less. 

Fever. — The  temperature  is  usually  elevated  in  the  begin- 
ning of  the  disease  to  102.5°  to  104.8°  F.  Other  symptoms  of 
fever  such  as  languor,  lowered  head,  disinclination  to  move, 
rough  hair  coat  and  sometimes  chill  are  noted.  When  the 
abscesses  are  evacuated  the  temperature  drops. 

Swelling  of  the  Lymph  Glands. — Concomitant  with  the 
catarrhal  symptoms  a  swelling  appears  and  usually  in  the 
intermaxillary  space.  In  most  cases  the  swelling  is  edema- 
tous, hot,  painful  and  fills  the  space  between  the  jaws,  and 
tends  to  suppurate,  becoming  "ripe"  in  four  to  eight  days. 
In  other  cases,  notably  in  older  horses,  and  in  patients  which 
have  suffered  previous  attacks  of  strangles  the  swelling  is  not 
marked  and  does  not  lead  to  abscess.  ( 'ommonly  the  abscess 
opens  spontaneously  in  six  to  ten  days. 

Dysphagia. — F>om  the  attending  pharyngitis  the  patient 
will  hold  the  head  extended  and  through  the  nostrils  water, 
saliva  or  even  solid  food  j)articles  arc  discharged.  From  the 
mouth  saliva  drools.  The  appetite  is  more  or  less  impaired, 
depending  on  the  severity  of  the  attack.  The  patient  will 
often  refuse  concentrates  (oats,  corn)  but  eat  some  ha\'  or 
grass.     The  thirst  is  not  increased. 

The  Respirations. — If  the  disease  is  confined  largely  to  the 
nasal  mucosa,  the  respirations  remain  about  normal.     When 


STRANGLES— CORYZA  CONTAGIOSA  EQUORUM      361 

the  laryngeal  or  bronchial  mucous  membranes  are  much 
swollen,  dyspnea  with  dilation  of  the  nostrils  occurs,  the 
frequency  often  as  high  as  25  per  minute. 

The  Pulse. — The  pulse  in  the  beginning  of  the  disease  is 
not  much  affected  but  later  may  reach  70  or  higher. 

The  Conjunctiva. — Frequently  in  the  earlier  stages  there  is 
a  flow  of  tears,  and  later  a  thick  mucous  discharge  from  the 
inner  canthus  of  each  eye.  In  mild  cases  this  symptom  may 
not  appear. 

Irregular  Strangles  {Bastard  Strangles). — In  nearly  every 
enzootic  of  strangles  some  cases  develop  which  differ  in  symp- 
tomatology from  the  typical  form  described.  The  principal 
difference  between  the  regular  and  irregular  types  of  strangles 
lies  in  the  fact  that  in  the  latter  the  abscesses  develop  by  way 
of  metastasis  in  parts  of  the  body  other  than  in  the  submax- 
illary region.  In  irregular  strangles  any  part  of  the  organism 
may  be  elected  as  the  seat  of  an  abscess,  although  IjTnph 
glands  are  most  apt  to  be  involved. 

For  practical  reasons  only  the  most  common  seats  will  be 
considered.  They  will  be  grouped  according  to  the  part  of 
the  body  in  which  they  appear. 

Head. — (a)  Abscess  in  the  pharyngeal  Ijniph  glands. 
When  these  glands  are  involved  there  develops  in  the  sub- 
parotid  region  a  swelling  which  may  be  quite  extensive.  It 
may  reach  the  upper  surface  of  the  larynx,  displacing  the 
organ  ventrally,  and  cause  dyspnea.  As  the  pharyngeal 
l\Tnph  glands  lie  on  the  lateral  surface  of  the  pharynx,  their 
enlargement  may  interfere  with  swallowing.  A  spontaneous 
rupture  of  the  abscess  may  occur,  the  pus  discharging  into  the 
pharynx  (sudden,  profuse  nasal  and  mouth  discharge)  or  into 
the  guttural  pouches  (sudden  disappearance  of  the  swelling, 
copious  nasal  discharge,  dysphagia) . 

(6)  Abscess  in  the  anterior  cervical  lymph  glands.  This 
causes  swelling  in  the  region  of  the  thyroid  glands.  Fluctua- 
tion is  usually  present.  The  abscess  usually  bursts  outwardly, 
although  it  may  rupture  into  the  gullet  and  lead  to  esophageal 
fistula.  If  the  adjacent  omohyoid  muscle  becomes  infiltrated 
with  pus,  dysphagia  and  aspiration  (foreign-body)  pneumonia 
can  follow. 


302      DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

(c)  Abscess  in  the  sul)lingual  glands  leads  to  swelling  of  the 
tongue.  The  organ  may  be  so  swollen  as  to  protrude  from 
the  mouth.  After  bursting  of  the  abscess,  the  edema  of  the 
tongue  rapidly  subsides. 

{d)  The  superficial  lymph  glands  and  vessels  of  the  skin  of 
the  head  may  become  involved.  In  this  case  in  the  regions 
of  the  eyes,  nose,  cheeks  and  lips,  painful  strands,  the  size 
of  a  slate-pencil,  and  surrounded  by  indurated  tissue,  are 
noted.  Later  nodules  form  along  the  course  of  the  swollen 
lymph  vessels.  They  finally  erupt  and  discharge  pus.  In 
individual  cases  considerable  swelling  of  the  head  occurs 
leading  to  severe  dyspnea. 

(e)  Abscesses  in  the  facial  sinuses  may  form  and  lead  to 
empyema  or  very  rarely  to  meningitis. 

Body. — {a)  Abscesses  in  the  subcutaneous  lymph  glands  of 
the  body  rarely  occur  in  the  region  of  the  withers.  Hanks,  etc. 

(6)  Abscesses  may  form  in  the  mammary  glands,  involving 
one  or  both  halves  of  the  udder.  In  stallions  scrotal  abscesses 
have  been  observed.  , 

(c)  The  perianal  lymj^h  glands  are  sometimes  elected,  caus- 
ing retention  of  feces  and  symptoms  of  proctitis. 

Limbs. — (a)  Abscess  may  form  in  the  axillary,  inguinal  and 
popliteal  lymph  glands.  While  they  usually  heal  readily, 
occasionally  they  are  obstinate  and  induce  lameness  of  con- 
siderable duration.  This  is  especially  true  of  popliteal 
abscesses. 

(b)  Abscess  of  joints  (purulent  arthritis)  is  not  common. 
One  or  more  joints  may  be  attacked.  When  the  leg  joints 
are  involved,  there  is  severe  lameness. 

Internal  Abscesses. — (a)  Abscesses  of  the  posterior  cervical 
lymph  glands  (jM'cpectoral)  sometimes  rupture  inwardly,  i)ro- 
ducing  purulent  ])leuritis  and  ])neumonia.  rronouncod  dysj)- 
nea  and  the  usual  signs  on  ])ercussion  and  auscultation  of  the 
thorax  are  noted  on  physical  examination. 

(6)  Metastatic  lung  abscesses.  The  symptoms  of  ])neu- 
monia  (cough,  purulent  nasal  discharge,  temperature,  auscul- 
tation and  percussion)  indicate  the  condition. 

(c)  The  mesenteric  lymph  glands.  These  glands  may  be 
primarily  or  secondarily  involved.     The  symptoms  are  fever, 


STRANGLES— CORYZA  CONTAGIOSA  EQCORUM      363 

mild  colic  and  a  history  of  exposure  to  strangles.  The  con- 
dition leads  to  death  either  gradually  or  suddenly  through 
rupture  of  the  abscess  and  the  resulting  peritonitis.  Similar 
symptoms  may  arise  from  abscess  formation  in  any  other  of 
the  lymph  glands  of  the  abdominal  cavity  whether  they  be 
parietal  or  visceral. 

Diagnosis. — The  recognition  of  the  usual  case  of  strangles 
is  not  difficult.  The  purulent  nasal  discharge  and  abscess 
formation  in  the  submaxillary  region  are  characteristic. 
Cases  occur,  however,  which  are  so  atypical  that  from  the 
clinical  symptoms  alone  a  diagnosis  is  impossible.  The 
history  of  exposure  to  strangles,  the  age  of  the  patient  and 
the  existence  of  more  typical  cases  on  the  same  premises  may 
assist  to  establish  a  diagnosis.  The  microscopic  examina- 
tion of  the  pus  (nasal  discharge)  for  streptococci  and  the  inoc- 
ulation of  experimental  animals  (white  mice)  are  frequently  of 
service  in  this  regard,  ^'ery  puzzling  are  those  cases  in  which 
the  abscesses  form  in  internal  organs  (lymph  glands  of  ab- 
domen), as  the  symptoms  are  often  vague.  The  history  of 
the  case,  the  tendency  to  attacks  of  mild  colic,  the  irregular 
temperature  and  the  presence  of  albumoses  in  the  urine  are 
suggestive  of  hidden  pus  of  probable  strangles  origin. 

Course  and  Prognosis. — ]Most  cases  of  strangles  heal  readily 
in  two  to  four  weeks  without  complication.  This  is  especially 
true  of  the  usual  benign  type  ("regular  form")  of  the  disease 
which  is  confined  largely  to  the  nasal  cavities  and  lymph 
glands  of  the  submaxillary  space.  On  the  other  hand,  when 
the  disease  assumes  an  atypical  ("irregular")  form,  affecting 
the  pharynx  and  its  lymph  glands  or  involving  internal  glands 
or  organs  (lungs,  mediastinal  glands,  mesenteric,  lumbar 
glands,  brain,  etc.)  the  course  is  greatly  protracted,  and  the 
prognosis  doubtful  to  bad.  ^Yhen,  after  the  submaxillary 
abscess  is  evacuated,  the  temperature  continues  up  or  rises 
again  after  a  temporary  fall,  the  development  of  further 
abscesses  is  probable.  In  some  cases,  as  the  abscesses  heal, 
fresh  ones  appear,  prolonging  the  course  and  complicating  the 
prognosis.  The  resistance  of  the  patient  and  its  surroundings 
are  important  factors  in  the  prognosis.  In  very  young  colts, 
especially  if  lacking  in  vigor  and  growth,  the  disease  is  much 


304       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

more  apt  to  be  fatal  than  in  colts  over  one  year  of  age.  Suck- 
lin.iis  are  not  infrequently  attacked  in  the  pharyngeal  lymph 
glands  leading  to  severe  dyspnea  and  serious  dysi)hagia  fol- 
lowed by  foreign-body  pneumonia.  When  the  patients  are 
neglected,  kept  in  damj),  dark,  dirty  stal)les  and  i)oorly  fed, 
the  course  is  longer  and  the  prognosis  not  so  good  as  when 
opposite  conditions  prevail. 

In  some  outbreaks  the  irregular  form  of  the  disease  domi- 
nates, involving  the  internal  lymph  glands,. especially  of  the 
abdomen  and  leading  to  death  from  peritonitis. 

The  mortality  is  1  to  3  per  cent,  in  the  benign  form  l)ut 
may  reach  20  to  30  per  cent,  in  malignant  outbreaks. 

The  most  frequent  sequehe  to  strangles  are:  (a)  Purpura 
hemorrhagica;  (b)  roaring;  (c)  empyema  of  the  sinuses  of  the 
head;  (d)  immobility  from  encapsuled  brain  abscess;  (e)  tabes 
mesenterica  from  chronic,  adhesive  peritonitis,  leading  to 
thickening  of  the  mesentery,  bowel  adhesions,  emaciation  and 
finally  cachexia. 

Treatment. — The  principal  factors  in  treating  strangles  are: 
(a)  Isolation  and  care  of  the  sick  and  subsequent  thorough 
disinfection  of  the  premises ;  (6)  proper  hygiene  (light,  cleanli- 
ness and  ventilation),  and  (c)  the  early  opening  of  the  ab- 
scesses. The  patient  should  be  placed  in  a  roomy,  light,  airy 
box  stall.  In  mild,  sunny  weather  the  patient  may  be  turned 
out  during  the  day.  The  feed  box  should  be  kept  clean  and 
free  from  accumulations  of  nasal  discharge.  The  diet  should 
consist  of  easily  digested  laxative  foods  (steamed  oats,  bran 
mashes,  grass,  carrots).  If  the  patient  refuses  all  food  and 
is  growing  weak,  milk,  eggs  and  alcohol  may  be  used.  Some- 
times appetite  may  be  stimulated  by  feeding  small  quantities 
of  oats  over  which  a  little  brown  sugar  has  been  strewn. 
Sucklings  should  be  assisted  at  nursing,  or  in  case  they  cannot 
suck  (dys])hagia),  rectal  feeding  may  be  employed.  Friction 
to  the  skin  through  good  grooming  is  helpful.  The  nostrils 
may  be  cleaned  with  cotton,  soaked  in  a  1.5  per  cent,  creolin 
solution  and  the  canthi  of  the  eyes  kept  free  from  pus  accu- 
mulation. 

The  abscesses  should  be  encouraged  to  "ripen"  by  hot 
fomentations.     Blisters  (biniodid  of  mercury  in  lard,  one  to 


STRANGLES— CORYZA  CONTAGIOSA  EQUORUM      365 

four)  are  occasionally  dangerous  (dyspnea  from  increased 
swellings).  As  soon  as  the  first  signs  of  fluctuation  appear, 
the  abscesses  should  be  opened,  using  a  long  incision,  and  the 
pus  discharged.  Once  evacuated,  and  thorough  drainage 
provided,  too  much  after-treatment  with  the  syringe  is  con- 
tra-indicated, as  it  prolongs  healing.  If,  following  the  open- 
ing of  the  abscess,  the  temperature  does  not  sink  in  the  next 
twelve  to  twenty-four  hours,  further  abscess  formation  may 
be  looked  for.  If  the  swelling  does  not  decrease  in  size,  a 
second  abscess  is  forming  in  the  neighborhood.  It  is  some- 
times possible  to  thwart  its  development  by  puncture  with  a 
finger  or  blunt  instrument  from  the  original  abscess  cavity. 
Abscesses  in  the  subparotid  region  may  be  opened  through 
Viborg's  triangle.  Pharyngeal  abscesses  are  frequently  deep- 
lying  and  can  be  reached  only  with  a  long,  blunt  instrument, 
such  as  the  metal  nozzle  of  a  syringe.     (See  Surgery.) 

If  dyspnea  develops  and  becomes  serious,  tracheotomy 
should  be  performed.  In  profuse  nasal  discharge,  steaming 
the  head  is  useful.  It  should  not  be  repeated  too  often,  as  it 
tends  to  produce  atony  of  the  mucous  membranes  of  the 
nose  and  throat.  The  use  of  intralaryngeal  and  intratracheal 
injections  (subnitrate  of  bismuth  5  per  cent.,  tannin  2  per 
cent.,  Lugol's  solution)  are  rarely  necessary  and  sometimes 
dangerous. 

Internal  medication  plays  a  secondary  part  in  the  treat- 
ment of  strangles.  Drug  treatment  should  be  expectative 
and  contingent  upon  the  arising  symptoms.  The  fever  and 
heart  are  treated  as  in  influenza  (see  this) .  AYhen  the  bowels 
are  inactive  small  doses  of  artificial  Carlsbad  salts  may  be 
used  (tablespoonful  in  feed).  The  catarrhal  symptoms  are 
treated  as  in  catarrh  of  the  air  passages  (see  this) . 

Of  late  antistreptococcus  serum  is  much  used  in  strangles. 
It  is  claimed  it  lessens  the  nasal  discharge,  shortens  the  term 
of  fever  and  prevents  complications  arising.  Further  sub- 
stantiation is  desirable. 

Protective  Inoculation.  Serum  Therapy. — As  an 
attack  of  strangles  usually  produces  immunity  lasting  for 
several  years,  attempts  have  been  made  to  artificially  immu- 
nize horses  against  the  disease. 


366       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

(a)  Active  Immunity. — Some  good  results  have  apparently 
been  obtained  by  the  use  of  bacterial  vaccines  in  the  preven- 
tion of  strangles.  For  this  purpose  either  dead  or  attenuated 
cultures  of  the  Streptococcus  equi  have  been  employed.  The 
use  of  the  non-attenuated  culture  i:)roved  too  dangerous. 

(/>)  Passive  Immunity. — A  polyvalent  antistreptococcus 
serum  has  been  employed,  but  as  the  Streptococcus  equi  is 
different  from  the  Streptococcus  pyogenes  of  man  and  animals 
it  proved  ineffectual  either  as  a  preventative  or  cure.  A 
serum  made  from  the  cultures  of  the  Streptococcus  equi  is 
said  to  have  given  better  results.  Acting  therapeutically  it 
diminished  the  nasal  discharge,  lowered  the  fever  and  stopped 
in  some  instances  further  development  of  the  abscess.  It  is 
employed  in  doses  of  10  c.c. 

MALIGNANT  HEAD  CATARRH  OF  THE  OX. 
(iAXGRENOUS   CoRYZA.      CoRYZA   GANGRENOSA   BOVUM. 

Definition. — A  non-contagious,  acute  infectious  disease  of 
the  ox  and  buffalo,  characterized  by  an  inflammation  of  the 
mucous  membranes  of  the  head,  leading  to  ulceration  and  the 
formation  of  pseudomembranes.  The  eye  is  also  involved 
and  nervous  symptoms  are  present. 

Occurrence. — Isually  occurs  sporadically  or  as  a  stable 
miasma,  especially  in  insanitary  barns.  The  disease  is  rela- 
tively rare  in  the  United  States,  but  outbreaks  have  been 
reported  from  Ohio,  New  York,  New  Jersey  and  Miimesota. 
The  disease  is  common  in  Europe. 

Etiology. — The  specific  organism  is  yet  unknown.  It  is 
assumed  that  the  virus  which  causes  the  disease  reduces  the 
resistance  of  the  body  tissues,  esi)ecially  mucous  membranes, 
through  toxins  which  it  eliminates.  The  ulcers  and  pseudo- 
membranes  may  be  due  to  secondary  invading  bacteria. 

Natural  Infection. — The  mode  of  infection  is  not  yet  under- 
stood. Probably  the  germs  harbored  in  damp,  dirty  stables 
contaminate  the  food  and  water  and  thus  be  taken  in  through 
the  digestive  tract.  Occasionally  the  disease  appears  among 
cattle  in  pasture,  but  usually  only  when  the  available  drinking 
water  is  foul. 


MALIGNANT  HEAD  CATARRH  OF  THE  OX         o()7 

The  disease  has  not  been  transmitted  by  inoculation.  It 
does  not  spread  by  contact.  In  some  stables,  as  noted,  it 
exists  for  years,  appearing  each  spring  and  fall  and  in  time 
causing  considerable  losses. 

Young,  fat  cattle  (one-  to  three-year-old  steers)  are  most 
often  attacked.  One  attack  does  not  produce  immunity 
against  subsequent  ones.  A  given  animal  may  suffer  suc- 
cessive attacks  a  few  weeks  or  months  apart. 

Symptoms. — The  period  of  incubation  is  from  twelve  hours 
to  two  days. 

The  disease  usually  begins  with  symptoms  of  fever  (104°  to 
107°  F.).  The  surface  temperature  is  unevenly  distributed, 
the  poll  of  the  head  hot,  the  muzzle  hot  and  dry.  The  fever 
drops  on  the  second  or  third  day.  Before  death  it  becomes 
subnormal. 

Nervous  Symptoms. — The  head  is  held  low  or  rests  on  the 
manger.  In  some  patients  on  the  second  or  third  day  there 
is  marked  stupor,  the  animal  lying  on  the  ground  unconscious. 

In  other  patients  there  is  excitement,  the  animal  bellowing, 
rearing,  and  plunging.  Locomotion  is  difficult,  the  gait  un- 
certain and  staggering.  Twitching  of  the  muscles  of  the  neck, 
shoulders  and  body  may  occur.  Epileptiform  spasms  have 
been  observed.  The  excitability  of  the  patient  is  increased  by 
such  external  influences  as  bright  sunlight,  sudden  noise,  etc. 

The  eyes  on  the  first  or  second  day  show  conjuncti\itis, 
which  may  extend  to  the  cornea  causing  keratitis.  There  is 
photophobia  and  profuse  lacrimation.  The  cornea  becomes 
turbid  or  ''milky,"  the  clouding  beginning  at  the  periphery. 
Iritis  and  cyclitis  are  also  observed,  the  anterior  chamber 
being  filled  with  yellow  exudate.  The  episcleral  bloodvessels 
are  congested.  From  the  fibrinous  iritis  the  animal  is  often 
blind. 

The  Respiratory  Tract. — There  is  at  first  a  thick,  viscid, 
purulent,  later  more  fibrinous  nasal  discharge,  mixed  with 
blood,  which  finally  becomes  discolored  and  fetid.  The 
croupous  masses  forming  in  the  larynx  narrow  its  lumen, 
cause  noisy  dyspnea,  and  at  times  distressing  cough.  The 
sinuses  of  the  head  may  })ecome  filled  with  exudate  and  the 
horn  core  inflamed,  leading  to  the  horns  becoming  loose.     In 


368       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

thrashing  about  the  patient  often  knocks  ofi'  the  loosened 
liorn. 

The  Digestive  Tract. — The  buccal  mucosa  is  early  red- 
dened. Later  in  the  course  of  the  disease  the  gums,  lips  and 
hard  palate  become  eroded.  Croupous  membranes  are  some- 
times noted  on  the  mucous  surface  of  the  lips,  cheeks  and 
palate.  The  animals  drool  and  fetid  croupous  masses  are  occa- 
sionally ejected  from  the  mouth.  There  may  be  dysphagia. 
The  appetite  is  impaired.  Water  is  drunk  in  small  quan- 
tities. The  bowels  are  constipated  during  the  height  of  the 
fever,  the  feces  tar-like.  In  the  latter  stages  there  is  diarrhea. 
The  feces  are  said  to  contain  fibrinous  masses  and  blood  in 
some  instances. 

Skin. — An  eczematous  eruption  (papulovesicular)  has  been 
observed.  The  skin  of  the  head,  especially  at  the  nostrils 
is  most  apt  to  be  involved,  although  the  coronets  may  be 
elected. 

Udder. — In  cows  the  milk  secretion  stops.  Rarely  a  coin- 
cidental mastitis  occurs. 

If  the  patient  live  several  days  it  emaciates  and  becomes 
anemic. 

Course. — The  course  is  acute.  The  initial  symptoms  usu- 
ally last  one  day.  In  three  or  four  days  the  disease  is  fully 
developed.  The  i)atients  rapidly  emaciate  and  generally  be- 
come unconscious  and  die  in  from  four  to  eight  days.  In 
some  cases  this  disease  may  be  prolonged  three  or  four  weeks 
and  end  in  recovery. 

Prognosis. — INIortality  (iO  to  90  per  cent.  Marked  nervous 
syni])t()ins,  high  fever  after  the  second  day  (pneumonia)  are 
bad  signs.  Those  animals  which  do  recover  are  left  with 
such  sequela'  as  blindness,  chronic  nasal  or  gastro-intestinal 
catarrh. 

Treatment. — This  is  largely  symptomatic.  («)  Cold  a])])li- 
cations  to  head  and  base  of  horns;  (h)  injecting  out  the  nos- 
trils with  antiseptics  and  removing  manually  the  membran- 
ous obstructions  to  breathing;  (c)  tracheotomy  in  apnea 
(do  not  be  in  a  hurry  to  remove  tube);^   (d)  trephining  the 

'  Of  very  questionable  value  in  practice. 


STOMATITIS  OF  CALVES— CALF  DIPHTHERIA      360 

frontal  sinuses  or  even  sawing  off  the  horns  and  irrigating  the 
cavities  through  the  opening;  (e)  alcohol  may  be  used  in 
great  mental  depression  or  strong  coffee  added  to  the  drinking 
water;  (/)  fever  may  be  reduced  by  antipyretics ;  (g)  consti- 
pation and  diarrhea  as  in  bowel  catarrh. 

The  poll  ax  is  indicated  in  severe  cases  (long  convales- 
cence; blindness,  etc.). 

NECROTIC  STOMATITIS  OF  CALVES.     CALF  DIPHTHERIA. 

Definition. — Calf  diphtheria  is  a  contagio-infectious  disease 
of  suckling  calves  in  the  course  of  which  there  develop  on  the 
buccal  mucous  membrane  croupous-diphtheritic  patches  and 
ulcers.  It  is  usually  attended  by  a  general  toxemia  which 
leads  to  death. 

Occurrence. — ^The  disease  is  very  common  in  Europe,  and 
serious  outbreaks  have  been  reported  in  the  United  States, 
particularly  in  the  western  States,  Colorado,  Wyoming,  South 
Dakota,  Iowa  and  southwestern  Texas. 

Etiology. — The  cause  of  the  disease  is  the  Bacillus  necro- 
phorus  of  Bang,  a  thin,  long  rod  which  forms  in  tissue  and  in 
artificial  media  slender,  undulated  filaments. 

Natural  Infection. — Probably  comes  from  the  calves  getting 
into  the  mouth  soiled  straw  or  litter  which  is  contaminated 
with  necrosis  bacilli.  Healthy  cahes  in  contact  with  dis- 
eased ones  are  infected  by  licking  the  sick  or  picking  up  matter 
contaminated  with  the  nasal  and  mouth  discharges  of  the 
affected.  The  disease  is  very  easily  transmitted,  spreading 
from  calf  to  calf. 

^'ery  young  calves  (three  to  five  days  old)  become  infected. 

Necropsy. — On  postmortem  in  the  mucous  membranes  of 
the  mouth  and  throat  are  found  areas  of  dirty  gray  or  brown 
color,  irregular  in  form  and  well  circumscribed.  They  are 
frequently  found  on  the  cheeks  and  borders  of  the  tongue, 
but  may  also  involve  the  upper  respiratory  passages,  and 
occasionally  the  intestinal  canal,  or  even  the  region  of  the 
coronet.  In  some  cases  large  surfaces  of  the  mucous  mem- 
brane are  co\'ered  with  a  yellowish-gray,  friable,  fetid,  cheesy 
mass.  Sometimes  the  lungs  are  infected,  in  which  purulent 
24 


;)7()       DISEASES  LOCALIZED  IN  CERTAIN  ORCANS 

or  caseous  foci  develop.  Occasionally  there  may  be  })k'uriti.s. 
In  some  instances  the  small  intestines  are  catarrhally  inflamed 
and  dotted  here  and  there  with  small,  pea-sized,  grayish- 
yellow  caseous  deposits.  The  spleen  is  not  enlarged,  though 
the  lymph  glands  are  swollen. 

Symptoms. — The  period  of  incubation  is  from  three  to  five 
days.  As  noted,  very  young  calves  are  most  often  attacked. 
The  first  symptoms  observed  are  languor,  disinclination  to 
suck,  and  slight  increase  in  temperature.  There  soon  de- 
velops a  drooling  from  the  mouth  and  slight  swelling  of  the 
cheeks.  The  examination  of  the  mouth,  which  is  painful  to 
the  patient  and  therefore  resisted,  reveals  that  the  mucous 
membrane  of  the  cheeks,  tongue,  hard  palate,  and  fauces 
show  areas  of  redness  and  erosion.  These  areas  represent 
patches  of  yellow  or  grayish-yellow  pseudomembranes  or 
ulcers.  The  patches  are  from  the  size  of  a  five-cent  piece 
up  to  a  silver  dollar  and  quite  irregular  in  form.  The  necrotic 
mass  is  very  adherent  to  the  underlying  tissue  and  can  be 
removed  only  with  difficulty.  It  may  be  an  inch  in  thickness 
and  involve  the  muscle  or  even  bone. 

The  disease  frequently  involves  the  nasal  cavities,  ])roducing 
a  yellowish  or  greenish-yellow,  sticky  discharge  which  adiieres 
closely  to  the  border  of  the  nostrils.  Occasionally  the  nose  is 
obstructed  by  accumulations  of  exudate,  causing  difficulty 
in  breathing.  If  the  larynx  and  trachea  are  involved  there 
will  be  cough  and  dyspnea.  Besides  these  local  symptoms 
there  are  those  of  general  toxemia,  such  as  loss  of  appetite, 
extreme  languor,  weakness  and  temperature  ranging  from 
105°  to  107°  F. 

Diagnosis. — The  diagnosis  is  not  difficult,  and  depends  upon 
the  fact  that  in  this  disease  well  marked,  thick,  necrotic  areas 
and  deep  ulcers  occur  upon  the  mucous  membranes  in  the 
regions  noted.  In  no  other  disease  of  the  calf  are  these 
deposits  so  marked. 

Course. — The  disease,  if  left  to  itself,  in  most  cases  leads  to 
death  in  five  to  eight  days.  Some  individuals  may  live  as 
long  as  three  weeks  and  then  die  of  pneumonia.  Cases  which 
recover  do  so  very  gradually,  convalescence  lasting  for  weeks. 
The  healing  of  the  ulcers  is  an  extremely  slow  process. 


LUXG  PLAGUE  OF  CATTLE  371 

Prognosis. — Calves  affected  with  necrotic  stomatitis,  if  left 
to  themselves,  usually  die,  or  if  they  recover,  remain  per- 
manently stunted  in  growth.  On  the  other  hand,  if  proper 
treatment  is  administered  early,  most  of  them  recover, 
healing  requiring  about  two  weeks. 

Treatment. — The  treatment  consists  in  thorough  cleansing 
and  disinfection  of  the  mouth  cavity.  Twice  daily  the  mouth 
should  be  syringed  out  with  a  2  per  cent,  creolin  solution  in 
warm  water.  The  patches  of  necrosis  may  be  scraped  oft'  or 
curetted  away  in  so  far  as  this  is  feasible.  After  the  sores  are 
irrigated  it  is  recommended  to  cover  them  with  a  paste  made 
of  one  part  salicylic  acid  and  ten  parts  glycerin  applied  with 
a  stick  or  brush.  Lugol's  solution  of  iodin  is  also  recom- 
mended. The  calf  may  be  allowed  to  suck  its  mother,  or  if  a 
weanling,  should  be  fed  liquid  food,  best  milk.  Plenty  of 
cool  water  should  be  kept  within  reach. 

Prevention. — The  sick  calves  should  be  separated  from  the 
healthy  ones.  The  mouths  of  exposed  calves  should  be 
examined  once  daily  for  lesions  of  necrotic  stomatitis.  Dis- 
infection of  the  stalls,  pens,  buckets,  etc.,  should  be  made, 
using  a  3  per  cent,  creolin  solution. 

LUNG  PLAGUE  OF  CATTLE.     CONTAGIOUS  PLEURO- 
PNEUMONIA OF  CATTLE. 

Definition. — Lung  plague  of  the  ox  is  a  specific  contagio- 
infectious  pleuropneumonia  which  may  assume  an  acute, 
subacute  or  chronic  form  and  is  due  to  a  filterable  although 
visible  virus. 

Occurrence. — The  disease  does  not  exist  in  the  United  States 
at  the  present  time.  In  1843  an  outbreak  occurred  in  New 
York  which  had  its  origin  in  an  infected  cow  imported  from 
England.  In  the  years  following  the  disease  spread  through- 
out the  country,  getting  as  far  west  as  the  ^Mississippi  River 
and  south  to  Virginia.  It  was  not  until  1892  that  it  was 
finally  entirely  stamped  out. 

Lung  plague  is  now  well  under  control  in  Europe,  although 
still  quite  prevalent  in  Spain.  Throughout  Asia  and  Africa 
the  disease  is  general.  Australia,  New  Zealand  and  Tasmania 


372       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

arc  infected.  In  the  Philippine  Islands  the  disease  is  witle- 
spread . 

Etiology. — Lung  plague  is  due  to  a  very  minute  micro- 
organism which  passes  through  coarse  porcelain  filters  but 
may  be  seen  under  the  microscope  when  magnified  over  1500 
diameters.  It  is  the  smallest  visible  microorganism  as  yet 
known,  being  almost  ultramicroscopic.  The  organism  has 
been  grown  in  artificial  media.  The  y'itwa  is  foimd  in  the 
pleural  exudate,  diseased  lung  and  in  nasal  discharge.  The 
blood  rarely  is  infectious. 

Natural  Infection. — Probably  tlirough  the  resjjiratory  tract. 
Experiments  to  i)roduce  typical  lung  plague  in  susceptible 
animals  l)y  inhalation  or  feeding  have  not  been  successful. 

The  disease  spreads  usually  by  direct  contact  with  infected 
animals.  Infected  and  emptied  stables  in  which  within  a 
year  sick  cattle  had  been  kept  are  common  sources  of  infec- 
tion. Where  cattle  are  crowded  together  in  a  barn  the  dis- 
ease spreads  most  rapidly.  On  the  other  hand,  however,  a 
rapid  spread  among  cattle  on  pasture  has  been  frequently 
noted. 

\Vry  commonly  a  supposed  recovered  ox  with  an  encap- 
suled  lung  focus  is  the  infecting  agent.  So  long  as  the  se- 
questered centre  in  the  lung  is  completely  encysted,  no  virus 
will  be  thrown  off,  but  once  a  communication  is  established 
with  a  bronchus  giving  the  ^■irus  exit  the  patient  becomes  a 
source  of  danger  to  healthy  cattle.  The  virus  may  remain 
virulent  for  two  or  three  years  in  a  lung  sequestrum  of  an 
apparently  healthy  ox. 

The  disease  is  more  prevalent  in  stable-fed  than  among 
pastured  animals.  It  ali'ects  all  breeds,  although  some  indi- 
viduals ])()ssess  natural  immunity. 

Necropsy. — As  a  rule  only  one  lung  (left)  is  invohed.  I'su- 
ally  a  large  area  is  hepatized.  On  cross-section  a  clear,  yellow 
fluid,  which  quickly  coagulates  flows  over  the  cut  surface. 
The  interlobular  connective  tissue  is  greatly  thickened,  form- 
ing yellow,  gelatinous  strands  one-half  inch  or  more  in 
thickness,  which  divide  the  lung  tissue  into  islands  of  varied 
color.  Characteristic  of  the  lung  lesions  are  the  different 
degrees  of  inflammation  which  a])pcar  at  the  same,  time  fresh 


LUNG  PLAGUE  OF  CATTLE  373 

areas  of  congestion  lying  beside  those  showing  red  or  gray 
hepatization  or  eAen  necrosis.  As  a  resnlt  the  cut  surface 
presents  a  distinctly  variegated,  marbled  appearance  very 
characteristic  of  the  disease.  The  bloodvessels  are  distended 
and  thrombosed.  The  corresponding  lymph  glands  are 
swollen  and  edematous. 

In  chronic  cases  the  proliferated  interlobular  connective 
tissue  is  almost  white  in  color  and  very  firm.  The  portions  of 
the  lung  they  surround  are  necrotic  and  sometimes  calcified. 
In  such  cases  a  thick  connective-tissue  capsule  may  inclose 
areas  from  the  size  of  a  walnut  to  a  grapefruit — so-called 
sequesters.  A  zone  of  reactive  infiammation  surrounds  the 
capsule.  The  pleura  shows  serofibrinous  pleuritis  which  can 
involve  the  pericardium.  Rarely  there  is  serofibrinous  peri- 
tonitis, especially  in  the  region  of  the  diaphragm  and  liver. 
In  calves  arthritis  of  individual  joints  and  a  gelatinous  infil- 
tration of  the  subcutis  (dewlap,  chest)  may  exist. 

Symptoms. — The  period  of  incubation  is  from  one  to  four 
weeks.  In  many  instances  it  appears  shorter,  the  early  symp- 
toms (temperature)  being  obscure  and  passing  unobserved. 
In  very  hot  weather  the  attack  is  often  more  sudden  and 
severe  than  in  the  cold  season. 

The  symptoms  are  very  \'aried.  From  a  clinical  standpoint 
usually  two  stages  can  be  recognized.  During  the  first  stage 
(so-called  occidt  stage)  a  peculiar  short,  weak,  painful  cough 
is  heard,  especially  after  drinking  or  eating  or  when  driven  up 
or  out  of  the  barn.  The  patients  are  languid,  show  capricious 
appetite,  suppressed  rumination  and  stand  with  back  arched, 
head  down  and  ears  pendent.  Driving  the  animal  induces 
dyspnea.  The  temperature  is  usually  somewhat  elevated  (one 
or  two  degrees) .  This  condition  may  exist  from  two  to  four 
weeks,  and  lead  to  recovery  or  the  symptoms  may  become 
more  pronounced.  Second  stage:  The  temperature  ascends 
to  104°  to  108°  F.,  and  severe  dyspnea  develops,  the  mouth  is 
held  open,  tongue  protrudes,  and  each  expiration  is  accom- 
panied by  a  loud  moan.  The  patient  usually  stands  with  its 
neck  extended  and  elbows  turned  out ;  if  it  lies  down  it  does  so  on 
the  afi^ected  side.  There  is  usually  complete  loss  of  appetite, 
suppressed  rumination  and  cessation  of  milk  flow.     There  is 


374       DISEASES  LOCALIZED  IN  CERTAIN  ORGANS 

often  a  mucopurulent  nasal  discharge  stained  with  1)1()(k1. 
The  feces  are  dark  and  dry;  later  a  profuse  fetid  diarrhea 
develops.  On  percussion  (which  is  painful)  over  the  affected 
side  an  extensive  area  of  dulness  may  be  detected.  On 
auscultation  bronchial  tones  and  rales  and  occasionally  fric- 
tional  sounds  are  heard.  If  the  consolidated  area  is  not  near 
the  lung  surface,  however,  percussion  and  auscultation  are 
negative.  The  abnormal  respirations  are  best  heard  after 
exercising  the  patient. 

In  fatal  cases  the  patient  rapidly  emaciates,  becomes  hide- 
bound, anemic,  cachectic  and  dies  of  exhaustion  in  three  to 
six  weeks. 

If  recovery  occur,  it  generally  takes  place  gradually  and  is 
not  always  complete,  the  patient  remaining  unthrifty  for  a 
long  time. 

Diagnosis. — Intra  vitam  a  positive  diagnosis  is  very  diffi- 
cult or  impossible.  Usually  only  a  careful  necropsy  will 
establish  beyond  doubt  the  existence  of  the  disorder.  A  clear 
history  of  the  prevalence  of  the  disease  in  the  country  or 
community,  the  insidious  onset,  the  fact  that  only  a  portion 
of  the  cattle  are  attacked  at  the  same  time  and  the  clinical 
evidence  of  pneumonia  are  ^'ery  suggestive  if  not  convincing. 

Lung  plague  can  be  confused  with: 

(a)  Hemorrhagic  Septicemia  (Pectoral  Form). — While  this 
disease  usually  has  a  sudden  onset,  is  much  more  acute 
and  attacks  larger  numbers  of  animals  simultaneously,  some 
acute  cases  of  lung  jilague  may  greatly  resemble  it  not  only 
clinically  but  on  necropsy.  In  doubtful  cases  only  a  bac- 
teriological examination  (finding  bipolar  bacillus;  animal 
inoculation)  will  determine. 

(6)  Tuberculosis  (Pulmonari/)  may  be  confused  with  a 
chronic  case  of  lung  plague.  The  absence  of  continued  fever, 
lack  of  pleural  symptoms,  the  even  more  chronic  course  of 
tuberculosis  and  the  results  of  the  tuberculin  test  usually 
suffice  to  differentiate  between  the  two.  However,  lung 
l)lague  and  tuberculosis  may  occur  concomitantlj'  in  the  same 
animal. 

(c)  Pneumomycosis  (.isijergillosis  of  the  Lungs)  is  rare  in 
cattle,  affects  most  often  birds.     The  develoi)mcnt  is  \ery 


LUNG  PLAGUE  OF  CATTLE  375 

slow;  little  fever.  On  necropsy  the  presence  of  Aspergillus 
fumigatus  in  the  bronchi  and  consolidated  lung  tissue  is 
conclusive. 

(d)  Vermi)wus  Bronchitis. — Affects  mainly  calves.  Cough- 
ing prominent.     Parasites  or  eggs  occur  in  the  ejections. 

Course. — ^The  course  of  the  disease  is  varied.  ]Many  cases 
recover  during  the  early  stage  and  after  only  a  few  days'  ill- 
ness. In  others  recovery  is  slow  and  often  imperfect,  pul- 
monary sequestra  remaining.  Such  an  animal,  as  noted,  is  a 
dangerous  source  of  infection. 

The  course  is  generally  more  stormy  in  young,  well-nour- 
ished patients,  although  calves  are  quite  resistant.  The 
mortalit}^  is  usually  from  60  to  70  per  cent.  Not  over  20  to 
30  per  cent,  fully  recover.  A  number  remain  chronically 
affected,  but  may  fatten. 

Depending  on  circumstances,  the  disease  may  persist  on  a 
given  premises  for  years.  This  is  particularly  true  where 
only  those  showing  clinical  sjTiiptoms  are  disposed  of,  no 
thorough  disinfection  practised  and  later  new  cattle  brought 
in  to  replenish  the  herd. 

Treatment. — Palliative  measures  are  rarely  successful  and 
generally  lead  to  the  further  spread  of  the  disease.  To  wipe 
out  lung  plague  all  sick  and  exposed  animals  should  be  slaugh- 
tered and  the  premises  they  occupied  (barns,  sheds,  etc.) 
thoroughly  disinfected.  Once  this  drastic  method  is  enforced 
the  disease  is  soon  entirely  eradicated.  In  the  I  niteed  States 
and  in  other  countries  where  it  no  longer  exists,  no  cattle 
should  be  imported  from  an  infected  country  without  passing 
through  a  strict  (ninety-day)  quarantine. 


CHAPTER  IV. 

INFECTIOUS  DISEASES  imOLVING  PRINdrALLY 
THE  NERVOUS  SYSTEM. 

TETANUS.     LOCKJAW. 

Definition. — Tetanus  is  an  acute  infectious  disease  due  to  an 
anaerobic  microorganism  which  produces  in  tlie  body  a  toxic 
])roduct  resembling  strychnin  in  its  physiological  action. 
The  disease  is  characterized  by  tonic  spasms  of  the  muscles. 
The  mind  of  the  patient  remains  undisturbed. 

Occurrence. — While  tetanus  has  a  wide  general  distribution 
it  is  confined  to  infected  districts.  Where  the  soil  has  become 
contaminated  with  the  germ  of  the  disease  it  is  of  common 
occurrence.  For  this  reason  it  is  more  prevalent  in  the 
tropics  than  in  northern  climes;  in  some  parts  of  the  country, 
commoner  than  in  others.  Horses,  swine  and  sheep  are  more 
often  attacked  than  other  domestic  animals.  The  disease  is 
more  prevalent  in  the  spring  and  fall  than  during  other  sea- 
sons. Since  the  use  of  antiseptics  has  become  more  general, 
tetanus  is  not  as  frequent  as  formerly. 

Etiology.-  The  disease  is  caused  by  the  Bacillus  tetani,  an 
anaerobic  rod-shaped  germ,  usually  carrying  a  spore  at  one 
end.  The  germ  occurs  in  the  spore  form  in  earth,  putrifying 
fluids  and  maiuur.  In  infected  districts  tetanus  spores  are 
normal  inhabitants  of  the  intestines  of  ruminants. 

Natural  Infection. — Infection  takes  place  through  a  fresh 
wound  into  which  the  spores  of  the  specific  bacillus  have 
gained  entrance.  Obviously  wounds  so  situated  as  to  become 
contaminated  with  soil  or  manure  are  most  apt  to  become 
infected.  Therefore  wounds  in  the  feet,  scrotum,  uml)ilical 
cord,  comi)ound  fractures  of  the  limb  bones,  tooth  cuts  and 
eye  wounds  are  most  dangerous  in  this  regard.  As  the  original 
wound  may  be  very  small  and  heal  by  first  intention,  it  cannot 


TETANUS— LOCKJAW  377 

always  be  found.  This  led  to  the  former  belief  in  *'  idiopathic 
tetanus."  In  cattle  tetanus  most  commonly  follows  parturi- 
tion where  rough  manipulations  have  been  made  to  relieve 
dystocia.  Newl)orn  animals  may  become  infected  through 
the  navel.  The  practice  of  docking  lambs  leads  to  tetanus, 
the  infection  entering  the  fresh  tail  stump.  Limited  enzootics 
of  tetanus  have  occurred  among  horses,  swine  and  sheep  where 
castration  without  sufficient  precaution  was  practised  in 
infected  districts. 

Necropsy. — ^There  are  no  constant  lesions  found  on  post- 
mortem. The  brain  and  cord  present  nothing  characteristic. 
The  condition  of  the  wound  through  which  the  infection 
entered  is  very  varied.  Usually  it  is  not  granulating  well 
and  there  is  little  pus  discharge.  The  nerves  are  often  bruised, 
congested  and  swollen.  If  the  infection  w^as  through  the 
umbilicus  (tetanus  neonatorum)  the  navel  may  be  inflamed. 

One  attack  of  tetanus  does  not  produce  immunity.  A 
given  animal  may  sufl^er  more  than  once  from  the  disease. 

Symptoms. — The  period  of  incubation  is  usually  from  one  to 
two  weeks.  A  minimum  period  of  twenty-four  hours  has 
been  noted  in  very  young  animals  and  exceptionally  in  older 
ones.  As  a  rule  the  disease  reaches  full  development  in  one 
or  two  days.  During  the  prodromal  stage  the, patient  is 
stiff,  does  not  care  to  move  and  shows  loss  of  appetite  or  at 
least  slow  mastication.  The  ears  are  held  erect.  If  the  head 
of  the  patient  is  elevated  a  protrusion  of  the  nictating  mem- 
brane over  the  eye  occurs,  a  symptom  most  pronounced  in 
the  horse.  Tetanus  may  be  partial,  involving  only  parts  of 
the  body  (partial  tetanus)  or  it  may  be  general,  affecting  the 
whole  body  (universal  tetanus).  In  some  cases  the  muscular 
spasms  are  confined  to  the  head  and  neck;  in  others  the  hind 
parts;  in  still  others  the  whole  body  is  involved. 

Horse. — When  the  symptoms  are  fully  developed  and  the 
reflexes  stimulated  by  excitement  the  patient  assumes  a 
characteristic  attitude:  The  legs  are  spread  and  stiff,  the  neck 
and  head  are  extended  and  the  tail  elevated.  The  ears  stand 
erect  approaching  each  other,  the  eyes  retracted  and  in  part 
covered  by  the  nictating  membrane.  The  pupils  are  dilated, 
the  nostrils  distended  and  the  nasal  wings  trumpeted.     The 


378         DISEASES  INVOLVING  NERVOUS  SYSTEM 

mouth  is  held  shut  with  tlie  commissures  drawn  upwardly. 
From  a  spasmodic  contraction  of  the  masseter  muscles  it  may 
be  impossible  to  open  the  mouth  more  than  a  fraction  of  an 
inch  (trismus).  Due  to  a  contraction  of  the  constrictors  of 
the  pharynx  dysphagia  and  ptyalism  are  ])resent.  While  in 
most  cases  the  back  is  held  straight  and  rigid,  occasionally  it 
is  arched  downwardly  (oi)isthotonos)  or  still  more  rarely 
curved  laterally  (pleurothotonos).  Locomotion  is  difficult, 
the  limbs  being  advanced  stiffly  and  the  feet  barely  raised 
from  the  ground.  It  is  almost  impossible  to  back  the  horse. 
The  muscles  are  tense  and  hard,  individual  muscles  standing 
out  prominently.  Twitching  of  the  muscles  is  a  symptom 
often  noted.  These  symptoms  may  subside  temporarily  pro- 
vided the  patient  is  in  no  way  excited.  However,  any  sudden 
noise,  a  flash  of  bright  light  or  an  unaccustomed  sight  will 
cause  the  spasms  to  return.  If  the  patient  is  struck  with  the 
hand  a  paroxysm  of  muscular  contraction  passes  over  the 
body.  The  mind  of  the  patient  is  clear,  although  the  face 
shows  anxiety  and  a  peculiar  rigid  stare.  Sometimes  in 
stallions  the  penis  is  erected.  The  pulse  is  small,  the  artery 
hard.  In  severe  cases  the  heart  beat  is  rapid  and  often 
palpitating.  The  respirations  are  increased  three  to  five 
times  their  normal  frequency.  As  the  blood  is  charged  with 
CO2  a  cyanosis  of  the  mucous  membranes  ajjpears.  The  lungs 
are  commonly  congested  and  edematous  so  that  rales  are 
heard  on  auscultation.  In  rare  instances  the  respirations  are 
noisy  or  pronounced  roaring  occurs.  As  swallowing  is  diffi- 
cult saliva,  food  or  drugs  may  enter  the  windpipe,  causing 
foreign-body  pneumonia  and  gangrene  of  the  lungs.  The 
temperature  is  affected  only  in  severe  cases  and  usually  just 
before  death  or  if  some  complication  has  set  in  (pneumonia, 
septicemia).  One  or  two  days  before  death  it  may  reach 
110°  F.  As  has  been  observed  in  other  diseases  accompanied 
by  severe  muscular  spasms  the  temperature  remains  high  for 
several  hours  after  death  (postmortem  temperature).  The 
appetite  usually  remains  good,  although  mastication  is 
labored.  Food  is  often  retained  in  the  mouth  or  coughed  out 
into  the  manger.  From  a  decomposition  of  the  unswallowed 
food  and  saliva  the  expirium  becomes  fetid.     A  regurgitation 


TETANUS— LOCKJAW  379 

of  liquids  and  solids  through  the  nostrils  is  not  uncommon. 
The  peristalsis  is  suppressed  and  defecation  is  difficult. 
Strangury  is  occasionally  present;  the  specific  gravity  of  the 
urine  is  high. 

In  tetanus  the  patient  usually  stands  during  the  course  of 
the  disease.  If  it  should  fall  to  the  ground  it  rises  with  great 
eft'ort  or  must  be  assisted  to  its  feet.  In  the  last  stages  the 
patient  usually  falls  to  the  ground  where  after  showing  violent 
muscular  spasms  it  dies  in  a  few  hours. 

In  local  tetanus  the  muscular  symptoms  are  confined  to 
the  muscles  nearest  the  point  of  infection  and  the  spasms  are 
not  severe.  Generalized  tetanus  is  usually  preceded  by  local 
tetanus. 

Ox. — In  cattle  tetanus  most  often  follows  obstetrical  opera- 
tions. The  s>-mptoms  are  usually  not  so  marked  as  in  the 
horse  and  are  sometimes  quite  vague.  The  reflexes  are  not 
much  increased,  the  animal  appearing  stupified  rather  than 
excited.  From  a  contraction  of  the  paunch  muscles  bloating 
commonly  occurs.  From  the  vulva  there  is  often  a  putrid 
discharge.     Emprosthotonos  has  been  observed. 

Slieep. — In  lambs  following  umbilical  infection  or  as  the 
result  of  castration  and  docking  tetanus  may  assume  an 
enzootic  form.  The  symptoms  in  sheep  are  much  like  those 
in  the  horse.     Opisthotonos  is  usually  well  developed. 

Swine. — In  swine  the  disease  commonly  follows  castration 
or  ringing.     There  is  usually  marked  trismus. 

Diagnosis. — The  characteristic  tonic  muscular  spasms,  the 
normal  mind  and  the  absence  of  temperature  speak  for 
tetanus. 

From  strychnin  poisoning  the  disease  is  distinguished  by 
the  fact  that  the  symptoms  of  this  poisoning  are  much  more 
acute  and  between  the  paroxysm  there  is  no  rigidity.  Tris- 
mus is  further  rarely  present  in  strychnin  poisoning  except  in 
the  last  stages. 

The  disease  might  be  confused  with  an  acute  muscular 
rheumatism.  However,  this  is  not  apt  to  occur  if  the  symp- 
toms are  carefully  noted.  There  is  no  prolapse  of  the  nictat- 
ing membrane  and  the  muscles  are  tender  on  palpation  in 
rheumatism. 


380         DISEASES  INVOLVING  NERVOUS  SYSTEM 

Tetanic  symptoms  have  been  noted  in  cases  of  intestinal 
irritation  in  the  liorse  (hie  to  the  {)resence  of  ascarides.  Tlie 
symptoms,  liowever,  are  very  mikl  and  the  case  usually 
yields  to  i)roper  treatment,  such  as  giving  a  vermifuge. 

Tetany  is  a  rare  condition  in  animals.  It  may  occur  when 
a  torn  or  severed  sensory  nerve  heals  in  the  lips  of  the  wound 
(castration). 

Course. — The  course  is  very  varied.  Some  cases  die  in  two 
or  three  days,  while  others  may  live  two  or  three  weeks  and 
the  disease  terminate  fatally.  Death  usually  occurs,  how- 
ever, in  three  to  ten  days  after  the  ap])earance  of  the  first 
symptoms.  Cases  which  terminate  fatally  usually  grow 
steadily  worse  from  the  beginning.  There  are,  however, 
exceptions.  Sometimes  the  patient  dies  suddenly  from  res- 
piratory arrest  or  the  aspiration  of  food  (oats)  when  recovery 
seems  probable.  The  coiu'sc  in  local  tetanus  is  benign  })ro- 
vided  it  is  not  complicated  with  trismus. 

Where  the  termination  is  favorable,  the  contractions  of  the 
muscles  become  less  after  the  second  week.  Convalescence 
usually  lasts  four  to  six  weeks. 

Prognosis. — The  mortality  in  tetanus  is  5.")  to  90  per  cent. 
The  disease  is  not  so  fatal  in  the  ox  as  in  other  animals.  In 
sheep  the  mortality  is  9o  to  100  per  cent. 

The  earlier  the  disease  appears  after  infection  and  the  more 
rai)idly  and  severely  the  sym])t()ms  develop,  the  more  fatal 
the  attack.  Fever  is  a  bad  sign.  Where  the  patient  is 
unable  to  eat  on  account  of  trismus  the  termination  is  usually 
fatal.  Severe  dyspnea  may  lead  to  hypostatic  congestion  of 
the  lungs  and  death.  On  the  other  hand,  if  the  case  develop 
gradually,  after  a  long  period  of  incubation,  and  the  sjinp- 
toms  of  generalized  tetanus  are  not  scA'ere,  no  fever  is  present 
and  the  appetite  retained  the  outlook  is  more  favorable. 
F^en  in  these  cases,  however,  the  ])rognosis  should  be  made 
with  caution,  as  fatal  complications  may  occur  at  any  time. 

Treatment. —  Ili/gienic. — The  patient  should  be  removed  to 
a  ([uiet,  darkened  stall.  There  is  no  objection  to  a  mare 
being  allowed  her  foal  or  a  horse  its  team  mate.  Idle  curi- 
osity seekers  should  be  kcj)t  away.  The  animal  should  be 
given  soft  food,  and  water  ke])t  within  constant  reach.     Slings 


TETANUS— LOCKJAW  381 

should  be  used  only  when  absolutely  necessary  to  keep  the 
animal  on  its  feet  and  where  the  temperament  of  the  patient 
permits  of  their  use.  If  there  is  difficulty  in  defecation  the 
feces  may  be  removed  from  the  rectum.  If  the  bladder  is 
distended  it  should  be  emptied  best  by  careful  pressure. 
While  theoretically  the  primary  wound  should  be  curetted 
and  disinfected,  in  the  horse  this  is  often  a  difficult  pro- 
cedure. Furthermore,  it  is  not  always  possible  to  find  the 
wound. 

Medical. — Internal  medication  is  of  little  avail.  On  ac- 
count of  the  danger  of  drenching,  drugs  should  be  given  as  far 
as  possible  with  the  food  and  water.  To  keep  the  bowels 
open  salts  may  be  administered.  Opiates  such  as  morphin, 
chloral  hydrate  and  the  bromids  afford  only  temporary  relief. 
Inhalations  of  chloroform  and  ether  just  before  a  meal  un- 
doubtedly assist  mastication  by  temporarily  relieving  the 
trismus. 

Subcutaneous  and  intramuscular  injections  of  phenol  solu- 
tions are  highly  recommended  by  some  authorities.  Sub- 
cutaneously  1  ounce  of  a  2  per  cent,  solution  or  2  drams  of  a 
10  per  cent,  solution  of  phenol  in  glycerin  may  be  admini- 
stered twice  daily.  One  dram  of  a  5  per  cent,  solution  may  be 
injected  into  the  muscles  of  the  neck  and  shoulders.  The 
injection  may  be  repeated  once  every  three  hours  for  the  first 
thirty-six  hours. 

Tetanus  Antitoxin. — The  administration  of  tetanus  anti- 
toxin, while  it  confers  temporary  immunity  against  the  dis- 
ease, has  not  proven  valuable  as  a  curative  agent.  It  is  most 
affective  when  used  early  and  in  subacute  cases.  As  a  cura- 
tive agent  3000  to  20,000  units  should  be  given.  This  amount 
may  be  split  into  several  doses:  For  instance,  20  c.c.  may  be 
used  for  the  first  dose  followed  by  15  to  20  c.c.  in  five  to  ten 
hours. 

Prevention. — Tetanus  may  be  prevented  by  thoroughly  dis- 
infecting all  fresh  wounds  and  by  the  use  of  small  doses  of 
antitoxin.  In  infected  districts  the  use  of  antitoxin  to  pro- 
duce immunity  prior  to  important  surgical  operations,  treat- 
ment of  fresh  wounds  (especially  punctured  feet  in  horses, 
castrations,  etc.)  has  proved  extremely  valuable.     In  coal 


382  DISEASES  INVOLVING  NERVOUS  SYSTEM 

mines,  where  general  tetanus  commonly  follows  foot  injuries, 
and  in  the  Panama  Zone,  a  badly  infected  district,  fi;ood 
results  have  been  obtained  from  antitoxin  used  as  a  preven- 
tative.    The  immunity  produced  lasts  about  one  month. 

RABIES.     LYSSA.     HYDROPHOBIA.     CANINE   MADNESS. 

Definition.  —Rabies  is  a  contagious,  generally  fatal,  in- 
fectious disease,  transmitted  by  the  bite  of  an  infected  animal 
and  characterized  by  delirium,  nervous  excitement,  and 
finally  paralysis.  Its  incubation  period  is  very  varied  and  no 
characteristic  macroscopic  lesions  are  found  postmortem. 

Occurrence. — The  disease  is  most  common  (SO  per  cent.)  in 
dogs  which,  when  infected,  inoculate  by  biting  other  animals 
(horses,  cattle,  sheep,  and  swine)  or  human  beings,  thus 
spreading  the  disease.  Rabies  occurs  in  nearly  every  coun- 
try in  the  world.  Australia  is  said  to  be  free  from  it,  and 
since  the  introduction  of  the  last  muzzling  law  in  1895  the 
disease  has  disappeared  in  Great  Britain.  Within  the  past 
ten  years  rabies  has  become  wide-spread  in  the  United 
States.  No  State  is  free  from  it,  but  accurate  statistics  as 
to  its  prevalency  are  not  available.  From  1900  to  1910 
it  was  reported  in  73  cities,  causing  the  death  of  230 
persons. 

Etiology. — Rabies  is  due  to  an  organism  whicli  in  certain 
stages  at  least  is  ultramicroscopic  and  passes  through  bacterial 
filters.  The  virus  is  found  in  the  tissues  and  fluids  of  the  in- 
fected body,  especially  in  the  central  nervous  system.  It  also 
occurs  in  the  saliva,  pancreatic  juice  and  milk,  occasionally 
in  the  aqueous  humor  and  has  been  found  to  exist  in  the  blood. 
The  muscles  seem  free.  In  1903  the  Italian  investigator,  Negri, 
discovered  in  the  protoplasm  of  certain  nerve  cells  of  rabid 
animals  small,  stainable  bodies  which  are  now  called  "Negri 
bodies."  They  were  demonstrated  in  9.")  to  98  per  cent,  of  the 
cases  of  rabies  examined,  and  are  rarely  found  in  old,  healthy 
dogs  (immunes).  It  is  probable  that  these  bodies  are  protozoa 
which  in  some  stages  of  their  development  are  small  enough 
to  pass  through  bacterial  filters.  Of  this,  however,  there  is  as 
yet  no  scientific  proof  available. 


RABIES— LYSSA— HYDROPHOBIA  3S3 

Natural  Infection. — Rabies  is  essentially  a  disease  due  to  the 
bite  of  a  rabid  animal  the  saliva  of  which  contains  virulent 
virus.  Such  saliva  coming  in  contact  with  any  fresh  wound 
could  produce  infection.  The  saliva  of  an  animal  may  be 
virulent  as  early  as  eight  days  before  the  termination  of  the 
period  of  incubation  and  before  s^Tuptoms  of  the  disease 
develop.  The  virus,  as  in  tetanus,  extends  along  the  nerves 
to  the  brain  and  cord.  It  may  also  be  carried  by  the  blood- 
and  h-mph  vessels.  The  danger  of  the  bite  of  a  rabid  animal 
depends  upon  the  virulency  of  the  saliva,  character  of  the 
wound  and  the  number  of  lymph  vessels  and  nerves  injured. 
Bites  inflicted  by  carnivorous  animals  are  more  dangerous 
than  those  produced  by  herbivora  on  account  of  the  form  of 
the  teeth  and  the  character  of  the  wound  they  produce. 
Wounds  near  the  brain  and  cord  are  especially  apt  to  be  fol- 
lowed by  infection.  In  horses,  bites  in  the  lips,  nose,  and 
cheeks  are  therefore  dangerous.  The  length  and  thickness  of 
the  hair  or  wool  covering  the  part  bitten  are  important  factors, 
a  heavy,  thick  growth  catching  most  of  the  saliva  and  pre- 
venting its  entering  the  wound.  Recently  shorn  sheep  are 
thus  much  more  susceptible  than  when  wearing  the  full  wool 
coat.  The  infected  wound  usually  heals  as  any  other  wound, 
quite  often  by  first  intention.  Infection  through  the  intact 
skin  has  not  been  demonstrated.  Not  over  .30  to  50  per  cent, 
of  the  animals  bitten  by  rabid  animals  take  the  disease. 

Necropsy. — There  are  no  characteristic  lesions  of  rabies. 
In  herbivorous  animals  fairly  constant  are  the  empty  stom- 
ach, congested  lungs,  and  larynx.  The  other  organs  are 
either  normal  or  show  secondary  lesions  not  directly  due  to 
rabies. 

Symptoms. — The  period  of  incubation  is  very  varied.  Gen- 
erally the  disease  breaks  out  two  to  eight  weeks  after  inocula- 
tion. ^Nluch  longer  periods  have  been  observed.  An  incuba- 
tion period  of  one  or  two  years  is  probable.  The  length  of 
the  period  is  determined  by  the  virulency  of  the  virus,  the 
character  and  location  of  the  w^ound,  and  the  age  of  the  ani- 
mal. Young  animals  are  more  susceptible  than  adult  or  aged 
ones.  In  general  the  symptoms  of  rabies  are  much  the  same 
in  all  animals.     They  are  modified  only  by  the  natural  pecu- 


384         DISEASES  INVOLVING  NERVOUS  SYSTEM 

liarities  of  the  different  species.  In  practically  all  animals 
are  obser\ed  psychic,  sensory,  and  motor  nervous  disturb- 
ances, the  absence  of  fever,  lost  or  perverted  appetite,  rapid 
emaciation,  and  fatal  termination.  The  psychic  changes  are 
shown  by  hyperesthesia  and  the  tendency  to  attack  other 
animals  or  even  persons  by  biting,  kicking,  or  horning  and  the 
continued  bellowing  in  cattle;  the  sensory,  by  the  licking, 
gnawing,  tearing,  or  rubbing  the  part  of  the  body  which  was 
bitten  (itching  of  part,  neuralgia)  and  the  motor,  by  hyper- 
kinetic symptoms,  such  as  clonic  spasms  or  twitching  of 
muscle  groups,  or,  on  the  other  hand,  by  akinetic  phenomena, 
as  sudden  dro])ping,  paresis  or  paralysis,  change  in  voice,  etc. 
The  perverted  appetite  is  recognized  by  the  fact  that  rabid 
patients  often  eat  their  own  dung  and  drink  their  own  urine 
in  preference  to  normal  food.  In  animals  two  clinical  types 
of  rabies  have  long  been  recognized:  (a)  the  furious  form, 
and  (b)  the  paralytic  (dumb)  form.  They  are  more  pro- 
nounced in  the  dog  than  in  other  animals.  Between  the  two 
types,  however,  intermediate  forms  are  noted,  so  that  clinic- 
ally many  cases  occur  which  do  not  clearly  belong  to  either 
type.  The  dumb  form  may  suddenly  change  to  the  furious, 
and  vice  versa.  In  dogs,  further,  three  stages  of  the  disease 
are  fairly  well  presented,  /.  e.,  tlie  stage  of  melancholia,  the 
stage  of  mania,  and  the  stage  of  paralysis.  They  are  best 
observed  in  typical  cases  of  the  furious  form  of  the  disease. 
In  the  other  domesticated  animals  they  are  rarely  well  de- 
fined. Rabid  animals  ra])idly  emaciate  and  almost  always 
die  within  ten  days  after  the  first  symptoms  appear. 

Ilorsc. — The  patient  is  first  noticed  to  rub  or  gnaw  the 
healed  bitten  wounds  (lip,  nose,  forelimb).  At  first  the 
friction  thus  applied  is  moderate,  but  later  in  the  disease  deep 
excoriations  and  severe  injury  to  the  part  rubbed  or  gnawed 
are  induced.  The  skin  of  the  metacarpus  may  be  torn, 
exposing  the  underlying  tendons  and  bones.  Naturally  swell- 
ing of  the  part  results.  The  patient  is  usually  quite  excit- 
able, restless,  ])awing,  alternately  lying  down  and  getting 
up,  symptoms  not  infrecpiently  mistaken  for  colic.  Biting 
into  the  manger,  stall  partitions,  etc.,  is  a  common  occurrence. 
The  lips,  gums,  and  c\cn  the  teeth  are  thus  injured,  as  the 


RABIES— LYSSA—H  YDROPHOBIA  3S5 

patient  disregards  caution  in  its  destructive  delirium.  If  a 
stick  be  presented,  the  horse  snaps  at  it  or  seizes  it  with  his 
teeth.  A  water  pail  may  be  seized  and  smashed.  In  some 
cases  slight  dysphagia  is  an  early  symptom,  saliva  drooling 
from  the  mouth;  in  drinking,  regurgitation  of  water  through 
the  nose  follows.  In  occasional  patients  marked  sjTnptoms  of 
fury  are  noted,  the  animal  rearing  wildly  into  the  manger,  and 
with  mouth  and  hoof  seemingly  trying  to  tear  the  stable  down. 
Blankets,  feed  boxes,  studding,  in  fact  anything  which  may 
come  in  the  way  are  torn  or  splintered.  Other  horses  or  even 
men  are  attacked  during  the  paroxysm.  In  stallions  and 
mares  increased  sexual  desire  is  noted.  The  appetite  is  per- 
verted, the  horse  ingesting  dung  and  urine.  A  change  of 
voice  also  occurs  in  horses,  but  is  not  as  marked  a  sjinptom  as 
in  dogs  and  cattle.  About  the  second  or  third  day  paralytic 
symptoms  appear,  the  patient  remains  down,  and  dies  in 
convulsions  or  coma.  In  some  cases  the  paralytic  symptoms 
are  not  preceded  by  a  stage  of  fury,  the  coiu'se  of  the  disease 
resembling  the  dumb  form  of  rabies  of  dogs. 

Ox. — Rabid  cattle  are  restless,  excited,  and  particularly 
aggressive  toward  dogs  and  fowls,  which  animals  they  pm'sue 
with  avidity.  Even  inanimate  objects,  if  in  motion  (a  rolling 
pumpkin),  are  chased  by  them  dog  fashion.  In  milch  cows 
milk  secretion  stops.  Not  infrequently  they  attempt  to  bite, 
seizing  the  coat  sleeve  of  a  person  standing  near.  The  patients 
have  an  anxious,  mischievious  exjjression,  and  quite  fre- 
quently a  peculiar  mo\ement  of  the  muzzle,  like  that  observed 
in  the  healthy  rabbit.  Sometimes  violent  contractions  of  the 
abdominal  muscles,  as  if  to  defecate,  are  seen.  Anything 
which  attracts  their  attention  they  rapidly  approach  and  try 
to  gore  and  climb  upon  with  their  forefeet.  A  common 
sjTnptom  is  a  sudden  loss  of  muscular  coordination  or  power 
which  causes  the  animal  to  drop  to  the  earth  as  if  "pulled 
down"  by  a  rifle  shot.  They  remain  down  but  a  moment  and 
spring  to  their  feet  again.  The  appetite  is  vitiated,  dung  and 
feces  being  licked  up  in  preference  to  good  food.  Water  is 
not  refused,  but  it  may  be  swallowed  with  difficulty.  Con- 
tinued bellowing  is  a  prominent  symptom,  the  sound  of  the 
voice  becoming  gradually  hoarser  and  fainter.  The  patients 
25 


386         DISEASES  INVOLVING  NERVOUS  SYSTEM 

from  day  to  daj^  grow  weaker  and  more  emaciated  and  finally 
get  down  and  are  nnable  to  rise. 

Death  usually  occurs  about  the  seventh  to  ninth  day.  In 
some  outbreaks  the  disease  takes  a  fatal  termination  in  three 
to  six  days. 

As  in  the  horse,  paralytic  symptoms  (dysphagia,  bloating, 
constipation,  paraplegia)  may  appear  without  being  preceded 
by  a  furious  stage.  The  patients  get  up  from  a  recumbent 
position  with  difficulty,  walk  with  a  staggering  gait,  show 
marked  ptyalism,  bellow  continuously;  food  and  water  are 
regurgitated  through  the  nose  and  mouth;  finally  they  lie 
prone  on  the  ground,  unable  to  rise,  show  spasms  of  the 
diaphragm  and  other  muscles,  and,  the  temperature  dropping 
below  normal,  die  in  five  to  seven  days. 

Sheej). — In  general,  the  symptoms  in  sheep  are  similar  to 
those  in  cattle,  although,  as  a  rule,  the  patients  are  not  as 
aggressive  and  destructive  in  their  tendencies.  A  very  com- 
mon symptom  is  increased  sexual  desire,  the  affected  sheep 
mounting  their  fellows.  Occasionally  aggressive  symptoms 
are  observed,  the  otherwise  shy  animal  attacking  by  butting 
the  other  sheep,  dogs,  or  even  persons  who  enter  the  pasture. 
Occasionally  they  try  to  bite.  The  disease  usually  lasts  three 
to  five  days,  and  ends  in  paralysis  and  death. 

Swine. — In  hogs  the  symptoms  are  quite  similar  to  those 
observed  in  dogs.  The  patients  are  very  restless,  keep  run- 
ning around  the  pen,  and  squealing  in  a  hoarse  voice.  They 
bury  themselves  in  the  straw  and  gnaw  the  parts  where  bitten. 
Sudden  noises  arouse  them,  and  occasionally  they  will  attack 
other  animals  and  man.  There  is  usually  profuse  ptyalism. 
Water  they  attempt  to  drink,  but  usually  cannot  swallow. 
Quite  commonly  young  pigs  will  come  together  head  on  and 
push  each  other  around  the  inclosure.  In  a  few  instances  the 
disease  resembles  the  dumb  form  in  dogs,  and  the  patients 
show  no  aggressive  sym})toms  but  are  simply  paralyzed,  un- 
able to  swallow,  show  changed  voice,  and  die  in  two  to  five 
days. 

Diagnosis. — Where  there  is  history  of  the  animal  having 
been  bitten  and  the  syin})tonis  of  the  diiVercnt  stages  well 
developed  a  diagnosis  intra  vitani  is  usually  not  difficult.     In 


RABIES— LYSS  A— HYDROPHOBIA  387 

the  furious  form  of  the  disease  the  aggressive  and  destructive 
tendencies  of  the  patient  are  very  suggestive.  However, 
these  symptoms  are  not  ahvays  present.  Occasionally  the 
diagnosis  is  extremely  difficult  and  cannot  be  made  during  the 
life  of  the  animal.  Generally  the  psychic,  sensory,  and  motor 
disturbances,  the  fatal  termination,  and  the  negative  post- 
mortem are  indicative.  As  a  rule,  however,  a  positive  diag- 
nosis can  be  made  only  by  microscopic  examination  or  experi- 
mental inoculation.  In  cases  of  doubt  it  is  best  to  confine 
the  animal  for  a  day  or  so  for  observation,  during  which  time 
there  usually  develop  sufficient  symptoms  to  make  the  diag- 
nosis highly  probable. 

The  microscopic  examination,  which  is  highly  valuable, 
consists  in  the  examination  of  properly  prepared  and  stained 
brain  tissue,  particularly  of  the  hippocampus,  medulla  ob- 
longata, and  cerebellum.  In  practically  98  per  cent,  of  the 
cases  of  rabies  which  died  or  were  killed  in  the  advanced 
stages  of  the  disease,  peculiar  cells,  the  so-called  Negri  bodies, 
are  found.  The  presence  of  the  Negri  bodies  indicates  rabies 
while  their  absence  tends  to  disprove  its  existence. 

Diagnostic  Inoculations. — An  emulsion  is  usually  obtained 
from  the  medulla  oblongata  of  an  animal  which  died  or  was 
killed  because  rabies  was  suspected.  This  is  injected  sub- 
cutaneously  or  subdurally  into  rabbits  or  sometimes  pups. 
Intra-ocular  and  intramuscular  inoculations  have  also  given 
successful  results.  Usually  in  from  two  to  three  weeks  after 
the  injection  the  experimental  animal  dies  of  typical  rabies 
provided  the  material  used  came  from  a  rabid  animal. 

Course  and  Prognosis. — The  disease  usually  lasts  four  to 
seven  days.  It  is  extremely  rare  for  it  to  exceed  ten  days  in 
any  animal.  While  a  few  recoveries  have  occurred  in  cases 
produced  by  artificial  inoculation,  authentic  records  of  re- 
covery from  natural  infection  are  wanting.  The  disease  is 
generally  fatal. 

Treatment.— Once  the  disease  is  fully  developed  no  treat- 
ment is  of  any  avail.  To  prevent  rabies  the  fresh  bitten 
wound  should  be  thoroughly  disinfected  with  a  8  per  cent, 
carbolic  acid  or  a  1  per  cent,  bichlorid  of  mercury  solution. 
If  the  wound  is  older  and  granulating  the  actual  cautery  or 


388         DISEASES  INVOLVING  NERVOUS  SYSTEM 

caustics,  such  as  stronj;  hydrochloric  acid,  sulphuric  acid, 
strong  ammonia,  etc.,  are  indicated.  Sulx-utaneous  injections 
into  the  tissues  adjacent  to  the  wound  may  be  helpful, 
liichlorid  (1  to  10,000),  or  1  per  cent,  carbolic  acid,  may  be 
used.  The  prompt  application  of  a  ligature  above  the  bite, 
if  applicable,  is  often  life-saving.  Generally  speaking,  how- 
ever, the  prevention  of  rabies  by  the  treatment  of  the  bitten 
wound  is  successful  only  where  it  has  been  applied  promptly 
and  within  the  first  fifteen  minutes  after  the  injury  is  made. 

The  preventive  treatment  as  commonly  practised  in  man 
consists  in  subcutaneously  injecting  the  patient  daily  for  a 
period  of  fifteen  to  twenty-one  da}'s  with  an  attenuated  virus, 
the  virulency  of  which  is  increased  with  each  successive 
injection.  This  is  commonly  spoken  of  as  the  Pasteur  treat- 
ment. It  is  occasionally  applied  in  veterinary  practice,  al- 
though on  account  of  its  cost  only  in  very  valuable  animals. 
Where  promptly  applied,  and  the  attenuated  virus  good, 
excellent  results  are  recorded. 

Prophylaxis. — Rabies  may  be  absolutely  prevented  by  doing 
two  things:  (a)  Inforcing  a  dog  tax  and  keeping  the  public 
thoroughfares  free  from  stray  dogs;  (b)  by  muzzling  all  dogs 
which  are  allowed  to  run  at  large.  That  these  measures  are 
only  successful  when  applied  to  an  extensive  territory  is  ob- 
vious. Applying  them  only  to  a  small  district  will  not  give 
beneficial  results,  as  a  rabid  dog  during  the  prodromal  stage 
of  the  disease  may  wander  far  and  wide,  biting  any  Vive  stock 
with  which  it  may  come  in  contact. 


CHAPTER  V. 
CHRONIC  INFECTIOUS  DISEASES. 

TUBERCULOSIS.     CONSUMPTION. 

Definition. — Tuberculosis  is  a  chronic,  contagio-infectious 
disease  due  to  the  Bacilhis  tuberculosis  and  characterized  by 
the  formation  in  the  different  organs  of  the  body,  of  small 
nodules,  nodes,  or  larger  irregular  areas  which  tend  to  case- 
ate,  undergo  fibroid  degeneration,  or  calcify. 

Occurrence. — Tuberculosis  occurs  in  all  domesticated  ani- 
mals, although  it  is  very  rare  in  sheep.  In  fact  all  warm- 
blooded animals  and  many  cold-blooded  ones  (fish)  are  sus- 
ceptible to  it.  In  man  one-seventh  of  the  race  die  of  it 
(150,000  annually  in  the  United  States  alone).  In  animals 
cattle,  swine,  and  fowls  are  most  commonly  infected.  The 
prevalency  of  bovine  tuberculosis,  as  in  other  contagious  dis- 
eases, depends  upon  the  opportunity  for  infection  and  spread. 
It  is  therefore  most  common  in  large  herds  confined  in 
stables  and  less  frequent  in  small  herds  living  in  the  open. 
In  the  western  ranges  of  the  United  States  and  in  the  great 
open  grazing  districts  of  other  countries  (steppes  of  Russia, 
South  American  pampas)  tuberculosis  is  comparatively  rare. 
On  the  other  hand,  in  the  more  densely  populated  parts  of  this 
country  (Atlantic  seaboard,  Middle  West,  neighborhood  of 
large  cities)  it  is  very  prevalent.  In  practice  a  greater  per- 
centage of  tuberculosis  will  be  found  in  dairies  and  in  herds 
of  full-blood  cattle  maintained  and  sold  for  breeding  pur- 
poses ("stud  or  seed  cattle").  In  both  instances  the  oppor- 
tunity for  infection  is  great  (indiscriminate  purchase  of  new, 
non-tuberculin-tested  animals)  and  the  close  contact  in  which 
cattle  of  these  classes  are  kept  still  further  favors  the  spread  of 
this  contagion.  While  every  State  in  the  Union  is  infected, 
in  some  districts  it  is  much  less  common  than  in  others,  and 
even  in  badlv  infected  districts  whole  herds  of  cattle  are  found 


390  CHRONIC  INFECTIOUS  DISEASES 

free  from  the  disease.  Modcru  transportation  facilities  are 
important  agents  in  spreading  the  disease  among  cattle.  The 
illegitimate  use  of  tuberculin  by  unscrupulous  ])ersons  is  a 
further  factor  in  the  s])read  of  bovine  tuberculosis.  Cattle 
reacting  to  the  test  are  frequently  sold  as  healthy  to  unsus- 
pecting buyers,  who  thus  introduce  the  disease  into  their 
herds.  Tuberculosis  of  animals  is  not  yet  as  prevalent  in 
the  Tnited  States  as  in  other  countries.  It  is  constantly 
increasing,  however,  especially  in  States  where  no  adequate 
measures  have  been  inaugurated  to  combat  it.  Swine  are 
infected  from  tuberculous  cattle  in  two  ways,  viz,:  (a)  By 
being  fed  milk  containing  tubercle  bacilli  and  (b)  by  feeding 
on  the  excrements  or  offal  of  tuberculous  cattle. 

The  prevalency  of  animal  tuberculosis  can  be  estimated 
with  approximate  accuracy  from  abattoir  statistics  and  the 
results  of  tuberculin  testing.  In  Germany  nearly  21  per  cent, 
of  the  cattle  and  3  per  cent,  of  the  swine  killed  for  food  have 
been  found  affected.  The  tuberculin  test  showed  over  50 
per  cent,  reacting.  Fully  25  per  cent,  of  the  cattle  of  Ger- 
many are  infected,  and  in  France  over  10  per  cent.  In  the 
United  States  1  per  cent,  of  the  cattle  are  found  tuberculous 
on  slaughter  and  2.5  per  cent,  of  the  hogs,  llesults  from  tu- 
berculin tests  on  400,000  head  of  cattle  gave  10  per  cent, 
reacting.  It  is  very  probable  that  1  per  cent,  of  the  beef 
cattle  and  10  per  cent,  of  the  dairy  and  stud  herds  of  this 
country  are  tuberculous. 

Etiology. — The  cause  of  tuberculosis  is  the  Bacillus  tuber- 
culosis of  Koch.  Three  types  of  this  bacillus  are  fairly  well 
defined,  viz.:  (a)  Typus  humanus,  (b)  typus  bovinus,  and 
(c)  typus  gallinaceus.     (See  Bacteriology.) 

Natural  Infection. — A  tuberculous  animal  can  spread  the  dis- 
ease only  by  throwing  off  tubercle  bacilli.  Such  are  spoken  of 
as  cases  of  "open  tuberculosis."  On  the  other  hand,  where 
the  animal  is  tuberculous  but  no  tubercle  l)acilli  are  passing 
from  it,  the  case  is  one  of  "  closed  tuberculosis."  Bacilli  may 
not  pass  continuously  from  "open"  cases.  "Closed"  cases 
may  at  any  time  change  to  "open"  ones. 

Modes  of  Infection. — Tubercle  bacilli  are  taken  into  the 
body:    (a)  via  digestive  tract  with  contaminated  food  and 


TUBERCULOSIS— CONSUMPTION  391 

water;  (6)  via  respiratory  tract  by  the  inhalation  of  tuber- 
cular spray  ejected  by  coughing  or  lowing  infected  cattle; 
(c)  via  genital  organs  during  coitus;  (d)  via  udder  through 
teat  canal;  (e)  via  wounds  (very  rare;  may  follow  castra- 
tion), and  (/)  congenital  tuberculosis  has  been  noted  only  in 
isolated  cases. 

(a)  Calves  and  swine  are  commonly  infected  through  milk 
from  creameries,  especially  skim  milk  obtained  by  centrifugal 
separation.  The  ingestion  of  cattle  excrement  by  swine  is  a 
pregnant  source  of  infection,  especially  in  America,  where  the 
practice  of  allowing  hogs  to  follow  cattle  is  much  in  vogue. 
The  feeding  of  the  offal  of  slaughter  houses  to  swine  is  likewise 
dangerous,  as  tuberculous  lungs,  livers,  lymph  glands,  gastro- 
intestinal contents,  etc.,  are  consumed. 

The  bronchial  exudate  of  tuberculous  cattle,  coughed  up  or 
otherwise  raised  from  the  lungs,  may  mix  with  the  saliva, 
and  thus  tubercle  bacilli  are  carried  to  feed  or  watering  troughs, 
bedding,  etc.  As  most  of  the  exudate  is  swallowed  by  the 
patient  (not  expectorated  as  in  man),  the  feces  become  pol- 
luted, scattering  bacilli  wherever  dropped.  Susceptible  ani- 
mals (hogs  and  cattle)  eating  or  drinking  substances  contami- 
nated by  such  discharges  become  infected.  The  same  would 
apply  to  any  other  secretion  or  excretion  containing  tubercle 
bacilli  (vaginal  discharge,  urine,  etc.). 

(b)  Infection  through  the  respiratory  organs  comes  from 
the  inhalation  of  either  (a)  globlets  of  bronchial  exudate, 
mixed  with  mucus  and  saliva,  which  are  coughed  out  or 
otherwise  forcibly  ejected  from  the  nose  and  mouth  of  tuber- 
culous cattle,  or  (b)  of  tubercle  bacilli  which  have  become 
partially  dried  and  are  adhering  to  dust  particles  floating  in 
the  air.  In  the  former  case  cattle  immediately  next  to  an 
"open"  case  of  tuberculosis  acquire  the  infection  by  close 
contact,  and  in  the  latter,  which  is  far  less  frequent,  by 
breathing  in  the  dried  bacilli  which  contaminate  the  in- 
spired air. 

(c)  Infection  by  coitus  may  occur  provided  the  genital 
organs  of  the  bull  (penis,  prostate,  testes)  or  cow  (vagina, 
uterus)  are  diseased.  This  form  of  infection  is  relatively 
rare,  but  more  common  than  generally  supposed. 


392  CHRONIC  INFECTIOUS  DISEASES 

(d)  Through  tht^  teat  canals  tubercle  bacilli  froiu  contami- 
nated bedding,  manure,  etc.,  may  reach  the  udder,  inducing  a 
primary  tubercular  mastitis.  A  general  infection  from  this 
source  is  seldom  noted. 

((?)  While  infection  through  skin  wounds  is  not  infrequent 
in  man,  in  animals  it  rarely  occurs.  In  swine  and  cattle  it 
has  been  observed  to  follow  the  use  of  raw  milk  applied  to 
fresh  castration  wounds.  Accidental  wounds  of  the  prepuce 
in  bulls  and  udder  in  cows,  in  contact  with  contaminated 
litter,  bedding,  etc.,  can  form  ports  of  entry  for  infection. 

(/)  Congenital  (intra-uterine  infection)  is  rare.  It  may 
occur  if  tuberculosis  of  the  uterus  is  present  and  in  advanced 
generalized  tuberculosis  (uterus  intact). 

Conceptional  or  germinal  tuberculosis  (infected  sperm  or 
ova)  has  not  l)een  proved. 

Modes  of  Eliminatiov. — In  cases  of  "open"  tuberculosis 
the  bacilli  may  be  eliminated  from  the  body  through  the  fol- 
lowing channels:  (<i)  By  cougliing  out  or  otherwise  ejecting 
infected  bronchial  exudate  through  the  nose  and  mouth; 
(b)  with  the  feces  contaminated  with  swallowed  bronchial 
slime  or  from  the  discharge  of  tubercular  ulcers  in  the  mucous 
memlirane  of  the  digestive  tract;  {cY  the  milk  will  contain 
tubercle  bacilli  if  the  udder  is  infected,  or  when  advanced, 
generalized  tuberculosis  is  ])resent,  and  the  udder  seems 
intact;  {d)  the  urine  contains  tubercle  bacilli  when  the  renal 
pelvis  or  parenchyma  is  tuberculous  or  in  tuberculosis  of  the 
reproducti\'e  organs  (\agina,  uterus,  ])rostate,  e])i(li(lymis), 
the  contaminated  exudate  or  secretions  afterward  mixing  with 
the  urine. 

Tuberculosis  is  essentially  a  stable  disease  in  that  the 
opportunity  for  infection  and  spread  is  greatest  where  ven- 
tilation, light,  and  cleanliness  are  inadequately  provided. 
Further,  in  stables  the  animals  are  in  closer  contact  with  one 
another  than  in  the  oj)en.  However,  tuberculosis  is  observed 
in  cattle  which  are  ne\er  housed  and  hogs  are  frequently 
infected  when  out  of  doors  following  tuberculous  cattle.  As  in 
other  contagio-infectious  diseases,  darkness,  dirt,  and  foul  air 

•  The  milk  of  apparently  healthy  cows  which  react  to  the  tui)erculiii  test 
ouly  occasionally  contains  tubercle  bacilli. 


T  UBERC  ULOSIS—CONS  UMP  TION  393 

are  conducive  to  the  propagation  of  tuberculosis,  while  the 
opposite  conditions  tend  to  inhibit  its  development.  For 
these  reasons  life  in  the  open  is  a  useful  preventive  and  cura- 
tive measure,  especially  in  the  earlier  stages  of  the  disease. 
In  advanced  cases  it  helps  relatively  little.     (See  Treatment.) 

Susceptibility. — As  noted,  tuberculosis  is  the  most  widely 
prevalent  disease  of  cattle  and  is  very  common  in  swine  and 
fowls.  On  the  other  hand,  horses,  dogs,  and  cats  are  seldom 
infected,  and  in  sheep  the  disease  is  extremely  rare.  A  high 
resistance  offered  to  tubercular  infection  may  be  racial  or 
individual.  It  is  believed  that  certain  breeds  of  cattle,  for 
instance,  are  less  predisposed  than  others.  The  semiwild 
strains  from  the  Russian  steppes  and  the  native  cattle  of 
Japan  seem  more  resistant  than  those  of  more  refined  origin. 
The  long-horn  of  Texas  and  the  West  was  apparently  an  im- 
mune. However,  the  opportunity  for  original  infection  and 
subsequent  spread  of  the  disease  has  been  much  more  difficult 
among  these  cattle  than  it  is  in  the  more  thoroughly  domesti- 
cated European  breeds  from  which  our  better  American  cattle 
sprang.  Among  the  tamer  breeds  (Jerseys,  Shorthorns,  etc.) 
no  racial  differences  in  resistance  have  been  noted.  The 
manner  of  caring  for  and  the  use  to  which  the  animal  is  put 
probably  has  as  much  to  do  with  the  susceptibility  to  tuber- 
culosis as  any  racial  peculiarity.  Selection  in  breeding  opera- 
tions with  only  precocity  in  development,  or  an  imnaturally 
great  milk  production  in  view,  to  the  exclusion  of  other  factors 
(good  constitution,  etc.),  will  produce  a  race  of  low  resistance 
to  any  infection.  If  tuberculosis  happens  to  be  the  disease 
to  w^hich  this  race  is  exposed,  infection  is  the  more  apt  to 
take  place. 

Individual  immunity  against  tuberculosis  is  commonly 
observed.  In  notoriously  infected  herds  a  few  animals  wdll 
sometimes  remain  healthy,  although  surrounded  by  every 
opportunity  to  take  the  disease.  Whether  this  immunity  is 
acquired  or  congenital  is  difficult  to  state.  Accurate  experi- 
ments to  determine  whether  or  not  it  may  be  handed  down  to 
future  generations  are  wanting. 

Necropsy. — The  lesions  of  tuberculosis  may  appear  in  any 
organ  in  the  body  with  the  exception  of  the  teeth.     The  loca- 


394  CHRONIC  INFECTIOUS  DISEASES 

tion  of  the  lesion  may  depend  npon  the  kind  of  aniniul,  mode 
of  infection,  and  whether  the  disease  is  primary  (local),  or 
secondary  (generalized).  In  the  ox,  tubercnlosis  is  usually 
confined  to  the  lungs,  serous  membranes,  and  lym])h  glands. 
In  swine  the  digestive  tract  with  corresponding  lymj^h  glands 
is  most  frequently  involved.  In  the  horse  the  lymph  glands 
(mesenteric,  retroperitoneal)  are  generally  elected.  How- 
ever, exceptions  to  this  rule  are  frequently  noted;  in  gener- 
alized (spread  via  blood)  tuberculosis  the  nodules  may  occur 
in  any  organ,  even  being  found  in  muscle.  The  influence  of 
the  mode  of  infection  is  difficult  to  determine,  since  it  has 
been  proved  that  subcutaneous  inoculations  in  calves  (even 
at  the  tail  tip)  with  tubercle  bacilli  were  followed  by  pul- 
monary lesions. 

The  most  characteristic  lesion  in  tuberculosis  is  the 
tubercle  which  has  undergone  caseous  degeneration.  The 
lesion  may  vary  in  size  from  a  small  millet  seed  (miliary 
tubercle)  to  a  cheesy  mass  larger  than  a  human  head,  due  to 
the  confiuence  of  numbers  of  smaller  foci.  ^Vhile  the  indi- 
vidual tubercle  is  at  first  of  a  translucent,  gray  appearance, 
later  from  the  degeneration,  which  begins  in  its  centre,  it 
assumes  a  yellow  color.  The  formation  of  nodules  tending  to 
caseate,  particularly  if  corresponding  lymph  glands  are  simi- 
larly affected,  is  characteristic  of  tuberculosis. 

Ox. — As  noted,  the  lungs,  serous  membranes,  lymph  glands, 
especially  the  bronchial  and  mediastinal,  are  most  commonly 
involved. 

Lungs. — In  the  lungs  nodules  or  nodes  of  varied  size,  of 
firm  to  fluctuating  consistency,  with  usually  well-defined  out- 
line, invade  the  tissue.  On  cut  surface  the  dry,  yellow, 
friable  caseation  surrounded  by  a  thick  ca])sule  is  found,  or, 
on  the  other  hand,  the  contents  are  soft,  puriform,  thick- 
fluid,  covered  by  a  thin  connective-tissue  layer.  The  color  is 
grayish  yellow  to  pronounced  yellow.  The  size  will  vary 
from  that  of  a  millet  seed  to  a  clenched  fist,  or,  by  confluence, 
a  whole  lobe  of  lung  tissue  may  be  found  changed  to  a  case- 
ous mass.  In  old  cases  calcification  of  the  tubercle  occurs, 
whereby  it  grits  under  the  knife  when  cut  through.  Usually 
in  the  neighborhood  of  a  larger  node  small  tuliercles  are  i)res- 


TUBERCULOSIS— CONSUMPTION  395 

ent.  While  the  hing  tissue  between  the  tubercles  is  often 
normal,  sometimes  the  intervening  alveoli  are  filled  with 
tubercular  exudate  and  the  interstitial  tissue  thickened.  By 
the  confluence  of  smaller  nodes  great  tubercular  masses  form. 
Sometimes  the  center  of  the  mass  is  hollow  (caverns),  but  more 
often  filled  with  friable,  dry  caseation  or  moist  pus.  Between 
some  of  the  cavities  and  bronchi  a  communication  forms 
through  which  a  secondary  infection  with  pus  cocci  or 
saprophytic  bacteria  takes  place,  In  some  instances  changing 
the  character  of  the  caseous  or  puriform  mass  to  that  of 
ichor,  causing  the  color  to  become  grayish  and  giving  it  a 
fetid  odor.  Tuberculosis  of  the  superficial  parts  of  the  lung 
often  extends  to  the  pleura,  leading  usually  to  circumscribed 
pleuritic  adhesions.  Very  rarely  a  diffuse  serofibrinous 
pleuritis  develops. 

In  calves  pulmonary  tuberculosis  assumes  the  form  of  a 
catarrhal  pneumonia.  On  cut  surface  the  hepatized  area  of 
the  lung  is  strewn  with  small,  round,  reddish-gray  to  yellow 
areas,  which,  by  confluence,  are  enlarged  to  caseous  centers 
the  size  of  a  hickory-nut  or  larger.  Bronchitis  almost  always 
attends  pulmonary  tuberculosis,  therefore  lesions  in  the 
bronchi  are  noted  on  postmortem.  The  signs  of  bronchial 
catarrh  with  bronchiectasis  are  common  findings,  the  dilated 
air  tubes  filled  with  mucus  or  cheesy  masses.  At  times  the 
bronchial  mucous  membrane  is  ulcerous.  The  trachea  is  less 
liable  to  ulceration  than  the  larynx.  In  the  latter  organ 
tumor-like  connective-tissue  growths  occur,  sometimes  almost 
entirely  occluding  the  lumen.  On  section  the  neoplasm  is 
found  to  contain  small  gray  or  yellowish  tubercles. 

Serous  Membrane. — The  pleura  is  most  frequently  involved. 
In  the  earliest  stages  reddish-gray,  small,  granules  develop 
surrounded  by  masses  of  connective  tissue.  On  section  of 
these  masses  areas  of  caseation  from  a  millet  seed  to  a  pea  in 
size  are  revealed.  By  confluence  and  simultaneous  connec- 
tive-tissue proliferation,  round  nodes  or  cauliflower-like  excres- 
cences protrude  from  the  serous  membrane.  The  protuber- 
ances may  have  a  broad  base  or  be  pediculated.  While  in 
consistency  they  are  at  first  soft,  later  they  become  firm  to 
hard.     The  tubercles  are  imbedded  in  the  growth  of  con- 


396  CHRONIC  INFECTIOUS  DISEASES 

nective  tissue  and  new-formed  bloodvessels,  where  they  case- 
ate  and  calcify.  By  confluence  great  polypoid  masses  several 
(•(Mitimeters  thick  occur,  ai)i)earing  not  unlike  a  bunch  of 
grai)os,  hence  the  old  name  "grape  disease."  Not  infre- 
ciuently  these  nodular  ])rotuberances  will  involve  the  peri- 
cardium and  cpicardium,  leading  to  adhesion  between  them. 
The  endocardiiun  and  valves  of  the  heart  are  rarely  involved. 

Lymph  Ghuids. — The  lymph  glands  corresponding  to  the 
afi'ected  organ  are  almost  always  tuberculous.  Not  infre- 
quently only  the  lymph  glands  are  diseased.  This  is  espe- 
cially true  in  young  animals  in  the  earlier  stages  of  the  disease, 
and  in  older  indixiduals  condemned  by  the  tuberculin  test. 
In  some  cases  the  lym])h  glands  on  the  surface  of  the  body, 
particularly  the  submaxillary,  subauricular,  prescapular,  and 
precrural  are  involved.  In  other  infections  the  supramam- 
mary  glands  are  elected.  The  tuberculous  lymph  gland  is 
often  enlarged  to  many  times  its  normal  size  and  presents  a 
nodular  surface.  On  section  it  will  be  found  to  contain 
tubercles  which  appear  either  as  round  or  irregular-shaped 
radiating  areas  of  caseation,  sometimes  surrounded  by  a 
capsule  of  connective  tissue,  and  often  calcified.  In  pul- 
monary tuberculosis  especially  the  mediastinal  and  j)eribr()n- 
chial  lymph  glands  are  diseased.  In  the  digestiA'e  tract  the 
suprapharyngeal,  mesenteric,  and  portal  lymph  glands  are 
elected.  The  glands  may  attain  the  size  of  a  double  clenched 
fist,  and  in  some  instances  interfere  with  the  functions  of 
organs  with  which  they  Come  in  contact.  Partial  occlusion 
of  the  esophagus  when  mediastinal  lymph  glands  are  involved 
is  often  observed.  The  mucous  membrane  of  the  digestive 
tract  may  show  nodules  or  ulcers.  As  a  rule  the  borders  of 
the  tubercular  ulcer  are  thickened  and  the  base  caseous. 
They  extend  into  the  submucosa  or  muscularis.  Usually  the 
environing  mucous  membrane  is  thickened  and  catarrhally 
inflamed. 

Liver. — Besides  tuberculosis  of  the  peritoneum  coxering  the 
liver,  in  the  i)arenchyma  of  the  organ  small  tubercles  or 
larger,  dry,  caseous  or  softer,  puriform  areas  are  noted.  As 
a  rule  the  nodes  and  abscesses  are  surrounded  by  connective- 
tissue  capsules.     In  some  instances  from  connective-tissue 


TUBERCULOSIS— COXSUMPTIOX  397 

proliferation  the  liver  may  attain  several  times  its  normal 
weight . 

Spleen. — Tuberculosis  of  the  spleen  is  usually  confined  to 
a  few  small  tubercles  scattered  through  the  parench\Tna  of 
the  organ.  The  spleen  is  usually  affected  in  young  cattle 
only. 

Kidneys. — A  tubercular  nephritis  is  common  in  old  cattle. 
In  the  parenchyma  of  the  kidney  caseous  tubercles  are  noted 
surrounded  by  connective-tissue  capsules.  By  confluence 
larger  nodes  form  which  may  proliferate  into  the  pelvis  of  the 
kidney.     The  ureters,  bladder,  and  urethra  may  be  involved. 

Genital  Organs. — In  male  animals  the  epididymis  and  the 
testes  are  most  frequently  elected;  in  the  female  the  uterus 
and  uterine  tubes.  In  the  uterus  round  tubercles  may  be 
palpated  in  the  early  stages,  but  later,  due  to  connective- 
tissue  proliferation,  the  walls  becoming  greatly  thickened 
and  rigid,  isolated  tubercles  may  not  be  felt.  Tubercles,  case- 
ous or  calcified,  of  grayish-white  color,  are  found  on  section. 
In  some  instances  superficial  tubercles  may  lead  to  ulceration 
of  the  uterine  mucosa. 

Udder. — Tiiberculosis  of  the  udder  appears  as  caseous  or 
calcified  nodes  in  the  parenchyma  of  the  organ,  usually  in  the 
neighborhood  of  which  smaller  foci  are  present.  As  a  rule 
only  the  hindquarters  are  affected.  In  some  cases  an  enor- 
mous enlargement  of  the. tuberculous  quarter  or  quarters 
occurs,  while  in  others,  on  the  contrary,  an  atrophy  is  noted. 
In  the  wall  of  the  milk  ducts,  milk  cistern  and  even  teat 
canals,  small  tubercles  find  their  seat,  the  lumen  being  filled 
with  a  chees\' detritus  and  sometimes  a  turbid  \ellowish-green 
fluid. 

In  recent  cases  of  embolic  infection  the  lobules  of  the 
quarters  concerned  are  swollen,  and  on  section  are  found 
strewn  with  grayish  tubercles,  the  intervening  connective 
tissue  showing  numerous  caseous  areas  from  the  size  of  a 
millet  seed  to  that  of  a  pea.  The  supramammary  l.Mnph 
glands  are  in  all  cases  tubercular. 

Tuberculosis  of  the  central  nervous  system,  bone,  joints 
and  muscle  is  relatively  rare  in  cattle.  It  is  seldom  that  the 
skin  tendons,  penis,  prostate  or  eye  form  loci  of  infection. 


398  CHRONIC  INFECTIOUS  DISEASES 

Acute  Miliary  Tiibcrculosi.s. — This  form  of  tuberculosis  is 
usually  seen  to  acc()mi)any  a  primary  lesion  from  which  it 
sprang  by  way  of  thrombosis  or  direct  eruption  into  a  blood- 
vessel. Not  infrequently,  in  the  same  lung,  along  the  course 
of  a  bronchus  is  found  a  large,  irregular-shaped  caseous  or 
calcified  primary  focus,  and  throughout  the  rest  of  the 
lung  tissue,  a  number  of  small,  round  tubercles  all  of  about 
the  same  size  and  alike  caseous  (secondary  foci).  These 
tubercles  are  usually  evenly  distributed,  and  each  surrounded 
by  a  red  zone.  In  the  liver,  spleen  and  kidneys  similar  lesions 
may  be  present.  The  corresponding  lymph  glands  in  miliary 
tuberculosis  are  always  acutely  swollen  and  their  cortical 
substance  abnormally  reddened. 

Symptoms. — Fully  90  per  cent,  of  the  cases  of  tuberculosis 
in  animals  present  no  clinical  symptoms.  As  long  as  the 
disease  is  local  and  does  not  seriously  involve  the  gastro- 
intestinal tract,  or  if  there  is  no  general  intoxication  of  the 
organism  with  the  toxins  of  secondary  infection,  a  remarkable 
destruction  of  parenchymatous  organs  may  follow  and  the 
patient  appear  healthy.  In  generalized  tuberculosis  or,  as 
noted,  if  the  bowels  are  much  involved,  or  sapremia  is  attend- 
ing, sjTnptoms  develop.  The  character  of  the  symptoms  is, 
however,  so  indefinite  that  they  caiuiot  be  relied  u])on  with 
any  degree  of  certainty.  Any  of  them  may  be  caused  by 
other  diseases  and  none  are  joathognomonic  of  tubercu- 
losis. 

Fever. — The  temperature  of  the  body  in  tuberculosis  is 
usually  not  disturbed  until  the  late  stages  of  the  disease,  wIumi 
fever  of  an  intermittent  or  remittent  type  sets  in.  Sometinu's 
the  temperature  is  higher  in  the  morning  than  in  the  evening. 
As  a  rule,  following  a  period  of  fever,  there  may  be  se\eral 
weeks  of  normal  tem])erature.  Only  in  the  last  stages  is  the 
fever  of  a  contiinious  type.  As  the  sym])toms  of  tubercu- 
losis vary  in  the  ditierent  domesticated  animals,  each  kind  of 
animal  will  be  considered  separately  as  follows: 

Ox. — The  period  of  incubation  after  artificial  infection  in 
bovine  tuberculosis  is  two  weeks  or  more.  Following  natural 
infection  it  is  probably  nuich  longer.  As  a  rule  months  or 
years  elapse  before  apj)reciable  symptoms  appear.     In  cattle 


TUBERCULOSIS— CONSUMPTION  399 

tuberculosis  inducing  clinical  symptoms  affects  the  following 
organs  or  tracts: 

(fl)  Lungs. — Cough  is  often  a  noticeable  s^Tnptom.  The 
cough  is  usually  short,  dry,  and  infrequent,  occurring  at 
first  early  in  the  morning  when  the  cattle  are  driven  up  to 
feed  or  milk.  Sometimes  moving  the  animals,  a  cold  drink 
of  water,  or  a  chilly  draught  of  air  (opening  the  stable  door) 
induces  it.  In  an  occasional  case  the  cough  is  paroxysmal. 
During  the  act  of  coughing  a  fine  spray  is  ejected  from  the 
nose  and  mouth,  and  following  it  a  viscid  bronchial  exudate 
is  swallowed.  Sometimes  a  portion  of  this  exudate  is  retained 
for  a  time  in  the  mouth  and  pharynx,  from  whence  it  may 
be  removed  with  the  hand.     (See  Diagnosis.) 

Dyspnea  is  usually  not  a  prominent  symptom  when  the 
patient  is  at  rest.  After  brisk  motion,  however,  the  respira- 
tions become  abnormally  rapid  and  labored. 

Percussion. — As  the  tubercles  in  the  lung  are  generally 
surrounded  by  air-containing  alveoli,  percussion  is  usually 
negative.  Only  when  large  areas  (at  least  10  cm.  broad) 
of  solidification  are  superficially  located  and  the  thoracic 
wall  relatively  thin  is  dulness  noted. 

Auscultation  is  very  often  negative.  Especially  after 
exercise  in  some  cases,  bronchial  breathing  and  rales  are 
heard.  The  rales  are  either  dry  or  moist,  depending  upon 
whether  the  exudate  is  tough-viscid  or  more  fluid  in  char- 
acter. Dry  rales,  as  a  rule,  predominate  and  are  heard  over 
the  whole  field  of  auscultation. 

If  the  pleura  is  also  involved  (tubercular  pleuritis,  pearl 
disease)  the  patient  may  show  pain  on  pressure  over  the 
ribs  and  percussion  induces  coughing.  Friction  sounds  on 
auscultation  can  rarely  be  distinguished.  Generally  the 
clinical  sjinptoms  of  tubercular  pleurisy  are  too  vague  to 
be  of  diagnostic  value. 

Appetite. — In  the  earlier  stages  the  appetite  is  retained, 
but  toward  the  end  (when  the  animal  becomes  emaciated) 
it  is  lost. 

Loss  of  Flesh. — In  the  later  stages  of  pulmonary  tuber- 
culosis the  animal  begins  to  lose  flesh  notwithstanding  good 
food  and  care.    The  hair  coat  lacks  luster,  becomes  erect  and 


400  CHRONIC  INFECTIOUS  DISEASES 

the  skin  feels  leather-like  and  thick.  In  time  emaciation 
is  in  evidence,  the  patient  very  anemic  and,  toward  the  end 
(usually  after  months),  cachectic. 

(h)  Larynx. — In  tubercular  laryngitis  palpation  of  the 
larynx  readily  causes  coughing.  In  some  cases  tuberculous 
growths  develop  in  the  lumen  of  the  larynx,  inducing  great 
dyspnea  and  even  suffocation.  As  swallowing  becomes 
difficult  the  animals  eat  little,  and  hence  fall  off  in  flesh. 

(c)  Lymph  Glands. — ^I'he  lymph  glands  may  be  primarily 
diseased  or  in  association  with  other  organs  (lungs,  udder, 
bowel,  etc.),  which  are  also  tuberculous.  The  following 
superficial  lymph  glands  are  most  commonly  elected:  sub- 
maxillary, subauricular,  prescapular,  precrural  and  supra- 
mammary.  The  glands  enlarge  to  form  tumor-like  growths, 
plainly  visible  on  the  surface  of  the  body.  They  may  attain 
the  size  of  a  large  potato,  are  round  or  oviform,  little  sensitive, 
firm,  nodular,  not  readily  movable  and  the  overlying  skin 
not  adherent.  In  calves  they  may  show  fluctuation  and  when 
incised  discharge  a  thick,  white  pus. 

Internally,  tuberculous  lymph  glands  may  interfere  with 
the  functions  of  organs  with  which  they  are  in  contact.  The 
mediastinal  glands,  if  much  enlarged,  may  depress  the  dorsal 
wall  of  the  esophagus,  constricting  its  lumen,  and  thus 
indirectly  lead  to  intermittent  bloating.  The  enlargement 
of  the  parapharyngeal  causes  dysphagia. 

(d)  Udder. — Usually  secondary.  In  the  latter  stages  there 
appear  in  the  hindquarters  firm,  painless,  not  well-ilefined 
nodular  enlargements  which  may  develoj)  into  hard  tumor- 
like growths  as  large  as  a  human  head.  In  some  cases  the 
\\'hole  quarter  or  quarters  may  be  swollen  to  enormous  size 
and  be  almost  of  the  consistency  of  stone.  Smaller  enlarge- 
ments (lumps)  are  best  i)alpated  after  the  udder  is  milked 
out.  The  supramammary  lymph  glands  are  increased  in 
size  to  sometimes  that  of  a  clenched  fist.  In  not  a  few  cases 
only  these  glands  seem  tuberculous,  the  udder  api)earing  intact. 

The  milk  is  usually  normal  in  appearance  for  a  long  time 
after  the  udder  is  involved.  In  the  late  stage,  however,  it 
becomes  mixed  with  tubercular  exudate,  is  watery  and  of 
greenish  color,  or  contains  white  Hoccuhe. 


r  I  BERC ULOSIS—CONS  UMP  TIOX  401 

(e)  Bowels. — The  only  tangible  clinical  symptom  of 
intestinal  tuberculosis  is  a  persistent  and  incurable  diarrhea. 
The  patient  usually  soon  emaciates,  becomes  cachectic,  and 
dies. 

(/)  Genital  Organs. — Peritunenni.^-A  remarkable  develop- 
ment of  peritoneal  tuberculosis  can  be  present  and  the 
patient  not  only  appear  in  health  but  gain  in  flesh.  In  cows 
tuberculosis  of  the  ])eritoneal  covering  of  the  ovaries  may 
induce  nymphomania,  the  animal  showing  almost  continuous 
estrum.    Later  the  patients  fall  off  in  flesh. 

(g)  Uterus. — The  most  constant  s;s'mptom  is  a  vaginal 
discharge  of  a  mucopurulent,  yellowish,  ichoric,  fetid  char- 
acter. Rectal  examination  may  reveal  the  greatly  thickened, 
rigid  wall  of  the  body  and  horns  of  the  uterus.  Failure  to 
conceive  (perpetual  bulling)  and  abortion  may  be  attending 
symptoms.     In  the  later  stages  sexual  desire  is  lost. 

(70  Vagina. — Hickory-nut  size,  yellowish  nodules  occur 
in  the  vaginal  walls  often  near  the  vulva. 

(/)  Testes. — ^There  appears  a  non-painful,  firm  swelling 
of  the  epidid,Miiis,  later  the  testes  become  enlarged,  forming 
a  swelling  of  considerable  size.  Hydrocele  is  a  common 
attendant  and  perforation  with  pus  discharge  is  not 
uncommon. 

SwiXE. — As  a  rule  there  are  no  clinical  s^'mptoms  of 
diagnostic  value.     The  disease  may  involve: 

(fl)  The  lymph  glands,  especially  those  of  the  tlu'oat, 
neck  and  prescapular  regions  (submaxillary,  pharyngeal, 
prepectoral,  etc.).  In  pronounced  cases  a  firm,  nodular, 
non-sensitive  swelling  of  the  throat  and  neck  appears  which 
may  be  extensi\'e  enough  to  interfere  with  mastication  and 
the  movements  of  the  head.  Occasionally  fluctuation  and 
perforation  with  the  discharge  of  thick  pus  or  cheesy  masses 
occur  in  some  part  of  the  swelling.  A  tendency  for  fistulse 
to  remain  is  noted. 

(6)  Lungs. — The  symptoms  are  much  like  those  of  the 
pulmonary  form  of  hog  cholera  and  consist  in  cough,  dyspnea, 
emaciation,  anemia,  cachexia  and  death  in  about  one  month. 

ic)  Bowels. — A  primary  intestinal  tuberculosis  in  pigs 
follows  feeding  with  infected  skim  milk  or  slaughter-house 
26 


402  CHRONIC  INFECTIOUS  DISEASES 

offal.  The  symptoms  are  similar  to  those  observed  in  cholera 
but  the  course  is  generally  longer,  the  animal  wasting 
gradually.  It  is  sometimes  possible  to  palpate  through  the 
abdominal  walls  firm,  nodular  enlargements  which  are 
either  tuberculous  lymi)h  glands  or  adherent  loops  of  diseased 
intestine.     Death  follows  months  of  decline. 

(d)  Bones  and  Joints. — ^The  vertebne  and  ribs  and  the 
joints  of  the  legs  are  most  commonly  attacked.  Rarely 
are  symptoms  noted  in  bone  tuberculosis.  In  tubercular 
arthritis  the  affected  joint  is  chronically  swollen  but  presents 
no  symptoms  of  acute  inflammation.  Lameness  is  usually 
present. 

Horse. — Tuberculosis  is  rare  in  the  horse  and  the  symj)- 
toms  are  usually  too  vague  to  be  more  than  suggestive. 
Briefly,  they  are  those  of  chronic  cough,  dyspnea,  early 
fatigue  when  at  work  and  intermittent  nasal  discharge 
(sometimes  bloody).  Percussion  and  auscultation  are  gener- 
ally negative.  Finally  the  animal  becomes  emaciated,  anemic 
and  cachectic.  In  colts  (fed  infected  cow's  milk)  a  tuber- 
culosis of  the  bowels  and  mesenteric  glands  has  been  observed. 
The  symptoms  are  not  characteristic.  The  colt  remains 
stunted  in  growth,  pot-bellied,  miay  show  periodical  attacks 
of  colic,  and  consti})ation  alternating  with  diarrhea.  On 
rectal  examination  enlarged  lymph  glands  may  be  palpated. 

In  adult  horses  polyuria  has  been  observed  in  some  cases. 
As  in  the  ox  enlargement  of  the  superficial  lymph  glands 
occurs.  Tubercular  ulceration  of  the  nasal  mucous  mem- 
branes is  very  exceptional.  The  temperature  in  equine 
tuberculosis  is  much  as  in  the  ox — intermittent  or  remittent. 
Morning  exacerbations  and  evening  remissions  in  the  course 
of  the  fever  have  also  been  observed. 

Diagnosis. — As  noted,  in  the  majority  of  cases  tuberculosis 
is  a  local  disease  in  animals  and  presents  no  clinical  symptoms. 
A  physical  examination  of  the  tuberculous  patient  will  there- 
fore reveal  nothing  to  indicate  the  presence  of  the  disease. 
Even  in  those  cases  of  a(hanccd  tuberculosis  the  symptoms 
are  too  vague  and  indefinite  to  be  depended  uj)on  with  any 
degree  of  certainty.  A  positive  diagnosis  of  tuberculosis, 
therefore,  from  the  clinical  symptoms  alone  is  not  tenable. 


TUBERCULOSIS— CONSUMPTION  403 

Other  aids  to  diagnosis  must  be  employed,  the  principal  ones 
of  which  are  the  following: 

1.  The  TuberciiJiii  Reaction. — Tuberculin  may  be  applied 
in  several  different  ways.  The  most  important  methods  of 
application  given  in  the  order  of  practical  importance  are 
the  following:  (a)  The  subcutaneous;  (fe)  conjunctival,  and 
(c)  dermal. 

(a)  The  subcutaneous  application  of  tuberculin,  which 
consists  in  injecting  the  tuberculin  in  proper  dosage  into  the 
loose  connective  tissue  under  the  skin,  is  as  yet  the  best 
known  and  most  reliable  method.  The  reaction  following  is 
general  in  that  it  induces  in  tuberculous  animals  (best  in 
cattle)  a  febrile  temperature  which  usually  begins  in  six 
to  eight  hours,  reaches  its  acme  in  twelve  to  twenty  hours, 
and  lasts  for  twenty-four  to  forty  hours  after  the  injection. 
(For  detail  of  technic,  interpretation,  etc.,  see  Malkmus' 
Clinical  Diagnostics.)  Tuberculin  properly  used  is  a  ver}^ 
reliable  diagnostic  agent.  In  98  per  cent,  of  the  cases  a 
positive  reaction  indicates  the  presence  of  a  tubercular 
lesion  which  can  be  determined  on  necropsy.  Tuberculous 
animals  may  not  react  to  the  test  under  the  following 
conditions : 

(1)  When  the  disease  is  in  the  period  of  incubation 
(Moore) . 

(2)  AYhen  the  progress  of  the  disease  is  arrested. 

(3)  In  advanced,  generalized  cases  and  the  condition  of 
the  patient  is  bad. 

(4)  ^Yhen  the  animal  has  been  just  previously  (within  four 
weeks)  injected  with  tuberculin. 

In  the  last  two  instances  cited  (3  and  4),  by  increasing 
the  dose  of  tuberculin,  a  reaction  is  apt  to  follow. 

(b)  The  conjunctival  application  consists  in  instilling  into 
the  conjunctival  sac  a  few  drops  of  tuberculin  (undiluted). 
In  tuberculous  cattle  in  six  to  twenty-four  hours  symptoms  of 
conjunctivitis  develop  (congestion,  swelling,  lacrimosis)  with 
the  accumulation  of  a  yellow,  fiocculent  exudate  in  the  inner 
canthus  of  the  eye.  The  reaction  may  last  two  to  four  days. 
It  is  spoken  of  as  positive  when  the  conjunctivitis  is  pro- 
nounced and  the  exudate  purulent.    Milder  reaction  (simple 


404  CHROMC   ISFECTIOVS   DISEASES 

catarrhal  conjunctivitis)  may  occur  in  healthy  iii<h\  ichials, 
cs])ccially  \vhere  full  strenf^th  tuberculin  has  hccu  used. 
Further,  in  healthy  cattle  the  api)licatiou  of  this  test  at  spaced 
intervals  will  often  induce  an  apparent  reaction  which  is 
very  confusing.  Sometimes  tuberculous  cattle  will  not  react. 
Negative  results,  therefore,  are  not  decisive. 

(c)  The  cutaneous  applications  of  tuberculin  consists  in 
either  rubbing  the  tuberculin  {(i)  into  the  intact  (shaved 
and  cleaned)  skin  (dermic),  ih)  painting  it  upon  the  scarified 
skin  (endcrmic)  or  (c)  injecting  it  into  the  substance  of  the 
skin  (intradcrmic),  probal)ly  l)est  into  one  of  the  skin  folds 
extending  from  the  tail-root  (tail  elevated)  on  each  side 
downward  to  the  anus.  In  tuberculous  cattle  the  p()siti^'e 
reaction,  modified  somewhat  by  the  method  of  application, 
consists  in  an  inflanunatory  (edematous)  swelling  which 
usually  appears  within  twenty-four  hours  and  often  lasts 
for  two  or  three  days.  When  the  skin  has  been  scarified, 
small  vesicles  sometimes  appear.  While  the  dermal  appli- 
cation of  tuberculin  may  furnish  valuable  contributory 
evidence  in  detecting  tuberculosis,  it  is  often  not  conclusive 
enough  to  be  relied  on.  Negative  results  are  not  always 
indicative  of  the  absence  of  tuberculosis.  However,  this 
method  of  ap])lying  tuberculin  is  still  in  the  experimental 
stage. 

2.  M  icro.scojjtc  Defer  mi  nation  of  Tnherrle  HuriUi  in  the  Secre- 
tions and  Excretions  or  in  Tissue  from  the  Suspected  Patient. — 
While  in  man  the  examination  of  sputum  for  tubercle  bacilli 
is  commonly  practised,  in  animals,  which  do  not  spit,  the 
method  is  not  so  feasible.  However,  milk,  manure,  urine, 
and  tissue  (portion Of  abscess  walls,  udder,  sui)erficial  lymph 
glands,  tuberculous  growths,  etc.),  may  be  subjected  to 
microscopic  examination  for  tubercle  bacilli.  Of  late  bron- 
chial slime  collected  with  special  devices  from  the  gullet 
(gullet  (lipi)cr)  and  trachea  (tracheotomy  tube,  wire  carrying 
sterile  gauze  at  end)  has  been  used.  In  cattle  this  method 
has  proved  of  service  in  detecting  oi)en  cases.  In  this  con- 
nection it  should  be  borne  in  mind  that  there  are  many 
other  bacilli  which  arc  "acid-fast,"  and  so  closely  resemble 
the  tubercle  bacilli  niorj)hologically  and  in  staining  properties 


rrBERcrLosis—coxsuMPriox  405 

that    a   dift'erentiatiun   with   the   microscope    is    impossible. 
(See  Bacteriology.) 

8.  BicKinostk  hwcukitious.—The  inoculation  ot  experi- 
mental animals  is  always  advisable  where  the  microscopic 
examination  has  been  indecisive.  The  guinea  pig  is  usually 
chosen,  as  it  is  very  susceptible  to  tuberculosis.  In  practice 
negative  results  in  this  animal  speak  for  the  absence  of 
tubercle  bacilli  in  the  suspected  material  injected.  Positive 
results  are  recognized  b\-  the  formation  of  a  true  tubercle 
which  appears  not  only  at  the  point  of  injection  but  spreads 
to  the  neighboring  lymph  glands  and  internal  organs  (liver, 
spleen,  lungs).  Acid-fast,  paratubercle  bacilli,  on  the  other 
hand,  induce  in  guinea-pigs  merely  a  local  lesion  at  the 
point  of  injection  which  does  not  tend  to  spread  from  the 
primary  focus.  The  inoculations  may  be  made  subcutane- 
ously.  intramuscularly,  intramammary  (in  nursing  females), 
andintraperitoneally.     (See  Bacteriology.) 

Course.— The  course  of  tuberculosis  in  animals  is  chronic. 
An  infected  calf  may  show  no  clinical  symptoms  until  it  has 
reached  maturitv  or  even  old  age.  Too  frequently  advanced 
tuberculosis  which  has  lead  to  the  near  destruction  of 
important  organs  (lungs,  liver)  or  caused  great  areas  of  the 
pleura  or  peritoneum  to  be  invaded  is  first  discovered  m  the 
slaughter  house.  Only  in  the  last  stages  of  the  disease,  and 
then  usuallv  due  to  the  invasion  of  secondary  organisms 
(pus  cocci),  is  it  possible  by  the  customary  methods  of 
phvsical  examination  to  recognize  the  disease  during  life. 
A  'sudden  generalization  of  the  disease  which  may  follow 
parturition,  an  attack  of  some  acute  disease,  exposure  and 
privation  is  sometimes  noted.  It  may  lead  to  death  in  a 
few  weeks.  As  a  rule,  however,  for  months  or  years  following 
infection  the  tuberculous  ox  seems  in  good  health.  Even  cases 
of  open  tuberculosis  may  appear  in  normal  health  and 
condition.  When  clinical  symptoms  finally  appear  their 
development    is    slow    and    the    decline    of    the    patient 

gradual.  i      i    u 

Tuberculosis  at  first  spreads  slowly  through  a  herd,  but 
with  each  new  victim  another  source  of  infection  is  supplied 
and  the  spread  becomes  more  rapid.     Finally,  but  usually 


40G  CHRONIC  INFECTIOUS  DISEASES 

after  years,  unless  something  is  done  to  cheek  its  advance, 
a  large  percentage  or  the  whole  herd,  irresi)ecti\e  of  age,  is 
infected. 

Prognosis. — (Generally  speaking,  the  prognosis  in  animal 
tuberculosis^ is  unfavorable.  While  undoubtedly  in  some  cases 
the  process  never  develops  beyond  a  few  local  lesions,  and  in 
others  it  may  become  arrested  (encapsulement  of  foci  of  infec- 
tion), in  the  majority  of  cases  the  disease  progresses  con- 
tinuously and  finally  leads  to  clinical  symptoms,  decline, 
and  death.  That  the  sanitary  conditions  surrounding  the 
tuberculous  animal  are  of  influence  in  the  earlier  stages  of  the 
disease,  there  is  little  doubt.  It  is  frequently  noted,  however, 
that  infected  cattle  kept  under  ideal  conditions  as  to  light, 
cleanliness,  and  ventilation  not  only  do  not  improve  in 
health,  but  actually  become  worse,  the  disease  making 
recognizable  progress  in  the  individual  and  in  the  henl. 
This  is  especially  true  if  open  cases  are  not  eradicated  but 
kept  to  infect  and  reinfect  their  companions. 

Treatment. — A  medicinal  treatment  is  useless.  In  man, 
light,  cleanliness,  and  ventilation,  coupled  with  rest  (especi- 
ally if  the  i)atient  has  fever),  have  checked  or  even  healed 
the  disease,  pro\  ided  it  was  not  too  far  ach'anced.  Whether 
similarly  good  results  are  obtainable  among  tuberculous  cattle 
has  not  been  adecpiately  demonstrated.  Too  few  scientific- 
ally conducted  ex])eriments  in  this  regard  have  been  made. 
Furthermore,  the  trouble,  ex])ense,  and  danger  of  treating 
individual  aniinals  would  be  prohibitive,  and  when  com- 
pared with  the  preventive  measures  now  employed  to  control 
and  eradicate  the  disease  (see  Prophylaxis)  become  in- 
significant. Repeated  injections  of  small  doses  of  tuberculin 
has  given  good  therajjcutic  results  in  man.  In  cattle  the 
expense  and  trouble  of  administration  make  its  use 
prohibitive. 

Prophylaxis. — (a)  Tuberculosis  may  be  ke])t  out  of  a  healthy 
cattle  herd  by  preventing  infected  individuals  from  coming 
in  contact  with  it.  The  disease  is  practically  always  intro- 
duced by  a  tuberculous  animal.  One  open  case  of  tuberculosis 
may  in  time  infect  a  whole  herd.  Therefore  all  cattle  brought 
into  the  herd  should  be  j)roven  free  from  tuberculosis  by  the 


TUBERCULOSIS— CONSUMPTION  407 

tuberculin  test.  (6)  Secondary  to  this  is  to  promote  a  high 
resistance  to  disease  in  the  individuals  constituting  the 
herd.  This  may  be  accomplished  by  proper  breeding, 
feeding,  good  sanitary  surroundings,  and  an  outdoor  life. 
It  would  be  still  safer  once  yearly  to  test  the  herd  with 
tuberculin. 

Eradication. — Tuberculosis  is  a  disease  which  is  spread 
practically  only  by  infected  individuals.  To  remove  these 
individuals  is  to  remove  the  source  of  infection.  ^Yhile  it  is 
true  that  not  all  tuberculous  animals  are  at  all  times  passing 
tubercle  bacilli  and  thus  spreading  infection,  in  practice 
any  attempt  to  differentiate  in  favor  of  one  case  of  the  disease 
as  against  another  (to  determine  whether  "open"  or  "closed") 
is  not  feasible.  A  tuberculous  ox  is  a  menace  and  constant 
source  of  danger  to  the  rest  of  the  herd.  It  should  therefore 
be  removed  from  all  contact,  direct  or  indirect,  from  its 
susceptible  companions. 

Generally  speaking,  there  are  two  methods  of  eradicating 
the  disease  in  cattle,  both  of  which  are  based  upon  the 
permanent  separation  of  the  diseased  from  the  healthy. 

A.  Radical  Method. — Commonly  used  in  the  United 
States,  and  where  the  disease  has  made  limited  progress. 
This  method  consists  in  testing  the  entire  herd  with  tuber- 
culin and  killing  the  reacting  animals  either  on  the  premises, 
where  the  carcasses  are  rendered  innoxious,  or  preferably 
in  a  central  slaughter  house,  in  which  the  carcasses  are 
passed  upon  in  regard  to  whether  or  not  fit  for  food  by 
competent  veterinary  inspectors.  Subsequently  the  premises 
(stables,  barns,  etc.),  are  thoroughly  cleaned  and  disinfected. 
This  method  is  certain  in  its  results  but  not  always  applicable. 
It  does  away  with  the  necessity  of  keeping  two  herds  (re- 
acting and  healthy),  and  the  rearing  of  the  calves  is  not  so 
cumbersome  as  with  the  palliative  methods. 

B.  Palliative  Methods. — («)  The  Bang  method.  Where  the 
number  of  animals  in  a  given  herd  is  too  great,  or  it  is  the 
desire  to  preserve  valuable  blood  lines,  a  less  drastic  method 
of  control  has  been  suggested.  It  is  as  follows:  All  clinical 
cases  of  tuberculosis  (lung,  bowel,  uterus,  udder)  are  taken 
out  of  the  herd  and  destroved.    Reacting  cattle  which  show 


408  CHRONIC  IXFECTIOfS   f)f.<iEASES 

no  clinical  evidences  of  the  disease  are  kept  separated  from 
the  cattle  which  do  not  react  to  the  tuberc-ulin  test,  and 
the  progeny  of  the  herd  is  reared  on  milk  which  is  free 
from  tubercle  bacilli,  either  by  feeding  it  sterilized  or 
allowing  the  calves  to  suckle  only  healthy  dams  or  nurse 
cows. 

(b)  The  Ostertag  method  differs  from  that  of  Bang  only 
in  that  the  original  herd  is  not  tested  with  tuberculin  and  no 
separation  of  the  diseased  from  the  healthy  is  made.  Clinical 
or  known  open  cases  are  removed  from  the  herd  and  all 
calves  are  reared  and  kept  entirel\'  isolated.  Twice  a  year 
the  herd  is  inspected  by  a  veterinarian,  but  not  tuberculined, 
and  clinical  cases  which  may  ha\e  developed  in  the  interim 
removed.  The  calves  are  tuberculin  tested  every  six  months, 
lieactors  are  removed  or  forbidden  to  be  bred.  The  milk 
and  feces  are  fre{iuently  examined  bacteriologically. 

Protective  Inocuhttion. — l)ej)ending  uj)()n  the  well-recog- 
nized fact  that  most  strains  (not  all)  of  tubercle  bacilli  of  the 
human  type  are  little  \'irulent  to  cattle,  attempts  have  been 
made  to  produce  immunity  against  bovine  tuberculosis  by 
inoculations  with  human  tubercle  bacilli.  Other  investi- 
gators have  used  attenuated  bovine  tubercle  bacilli  or  have 
enclosed  the  bacilli  in  vehicles  (colloidal  sacs)  to  ])revent  their 
being  taken  up  by  the  organism.  A  degree  of  innnunity 
has  thus  been  produced,  but  it  is  of  short  duration,  nine  to 
eighteen  months,  and  in  practice,  as  yet,  has  contributed 
little  toward  either  the  control  or  eradication  of  the  disease. 
A  certain  danger  attends  inoculating  cattle  with  tubercle 
bacilli  of  human  type  in  that  they  sometimes  i)roduce  lesions 
of  tuberculosis,  or  at  any  rate  are  so  slowly  eliminated  from 
the  body  (may  remain  alive  in  the  body  fi-om  two  to  two  and 
one-half  years)  that  the  use  for  food  of  the  animal  so  inocu- 
lated might  lead  to  infection  of  human  beings,  '^riiere  is  a 
further  possibility  that  the  milk  of  cows  so  treated  might 
contain  human  tubercle  bacilli,  'i'hc  following  methods  of 
bovovaccination  are  in  vogue: 

1.  von  Bchritufs  Bovovacclnc. — The  vaccine  is  made  by 
drying  tubercle  bacilli  (typus  humanus)   in  a   \acuum  and 


TUBERCVLOSrS—CONSUMPTIOX  400 

injectiiiii"  it  at  intervals  into  the  juu'nlar  \eins  of  calves. 
A  marked  resistance  against  subseciuent  artificial  inocnlation 
with  either  bovine  or  human  tuberculosis  was  acquired, 
but  it  lasted  no  longer  than  twelve  to  eighteen  months.  To 
repeat  the  vaccination  each  year  would  be  expensive  and  the 
consequent  elimination  of  bacilli  highly  infective  to  man 
makes  the  method  hazardous. 

2.  Kocli-Schiltz  Method. — Consists  in  injecting  an  emul- 
sion of  tubercle  bacilli  of  human  type  into  the  veins  of  cattle. 
Nearly  six  months  later  three  cattle  so  treated  were  still 
resistant  enough  to  overcome  highly  virulent  cultures  of 
bovine  tubercle  bacilli  with  which  they  were  inoculated. 
Subsequent  experiments  showed  the  immunity  produced  to 
be  short-lived,  not  lasting  a  year. 

3.  KJimmers  Method. — Two  strains  of  human  tubercle 
bacilli  are  employed,  one  which  has  been  attenuated  by 
heating  to  52°  C,  and  the  other  by  being  repeatedly  passed 
through  the  salamander.  The  bacilli  used  are  non-virulent 
(even  to  guinea-pigs)  and  passage  through  animals  does  not 
revive  their  pathogenic  properties.  The  vaccine  (called 
"antiphymatol")  is  injected  subcutaneously  (5  c.c).  The 
injection  should  be  repeated  at  least  once  a  year.  In  infected 
individuals,  where  it  is  said  to  have  therapeutic  value,  it  is 
given  every  three  months.  Hygienic  measures  (separation, 
removal  of  open  cases,  feeding  calves  sterile  milk,  etc.), 
are  recommended  to  accompany  the  vaccination. 

4.  Heymans  method. — Consists  in  inserting  under  the  skin 
of  cattle  a  gelatin  capsule  containing  tubercle  bacilli  (human 
or  bovine).  The  metabolic  products  of  the  bacilli  diffuse 
through  the  walls  of  the  capsule  and  are  taken  up  by 
the  hTiiph,  eventually  impregnating  the  whole  organism. 
Immunity  is  produced  and  in  tuberculous  animals  a  curative 
efTect  is  claimed.  Cattle  of  any  age,  whether  tuberculous 
or  not,  may  be  treated  by  this  method  (once  yearly  for 
durable  immunity),  for  which  good  results  are  attested  by 
the  originator. 


410  chronic  infectious  diseases 

Intestinal  paratuberculosis    johne's  disease. 

Specific  Chronic  Enteritis  of  the  Ox.     Chronic 
Bacterial  Dysentery. 

Definition. — A  chronic  contagious  disease  of  the  bowels  of 
cattle,  which  in  the  majority  of  cases  leads  to  intermittent 
diarrhea,  anemia,  cachexia,  and  death.  It  is  due  to  an 
acid-fast  bacillus. 

Occurrence. — The  disease  was  discovered  in  1895  by 
Johiie  and  Frothingham  in  Germany.  It  is  not  uncommon 
in  the  United  States.  Sporadic  outbreaks  and  enzootics 
have  been  reported  from  several  States.  England  and  the 
continent  of  Europe  are  badly  infected.  In  Switzerland  and 
Denmark  it  causes  considerable  losses.  It  is  probably  nuich 
more  pre\'alent  than  usually  suspected,  being  confused  with 
other  chronic  enterites  and  bowel  tuberculosis. 

Etiology. — An  acid-fast  bacillus  resembling  the  tubercle 
bacilhis  of  avian  type.  The  bacilli  are  found  in  the  intestinal 
mucous  membrane,  and  in  the  mesenteric  lymph  glands. 
The  germ  does  not  grow  artificially  unless  cultivated  on  a 
special  medium.  It  is  probably  distinct  from  the  tubercle 
bacillus.     (See  Bacteriology.) 

Natural  Infection. — The  causal  organisms  are  eliminated 
with  the  feces.  They  enter  the  body  of  a  susceptible  animal 
via  digestive  tract.  The  contagiousness  of  Johne's  disease 
has  been  proven  by  feeding  experiments  and  successful 
transmission  intravenously.  This  is  further  confirmed  by 
the  practical  obser\'ation  that  when  once  introduced  into  a 
herd  it  spreads. 

Necropsy. — The  cadaver  is  usually  emaciated.  The  lesions 
are  confined  to  the  bowels  and  mesenteric  lymi)h  glands. 
In  typical  cases  the  mucous  membrane  of  the  small  intestine 
and  occasionally  the  colon  and  cecum  is  greatly  thickened 
(sometimes  fourfold)  and  thrown  into  folds  or  convolutions, 
some  of  them  transverse,  some  longitudinal,  giving  the  bowel 
a  corrugated  api)earance.  Coating  the  affected  nnicosa  is 
a  turbid,  grayish-yellow,  slimy  exuflate  which  is  readily 
scraped  off.    The  surface  of  the  folds  is  usually  smooth;  the 


INTESTINAL  PARATUBERCULOSIS  411 

crevices  between  ragged.    Nodules  and  ulcers  do  not  occur 
The  mesenteric  glands  and  Payer's  patches  are  somewhat 

'lymptoms.-As  a  rule  only  adult  cattle  are  affected, 
although  occasionally  it  may  attack  yearlings  or  even  younger 
animals.  The  disease  develops  gradually  and  may  go  on 
for  a  vear  and  not  be  noticed.  The  most  promment  symp- 
toms "are  progressive  emaciation  and  anemia.  An  niter- 
mittent  diarrhea  is  an  almost  constant  symptom.  The  e^ces 
are  thin,  gruel-like,  or  watery,  and  dischai-ged  w  thout 
straining.  In  a  few  cases  there  may  be  no  diarrhea,  although 
the  emaciation  and  anemia  are  present. 

The  general  condition  of  the  patient  gradually  becomes 
bad.  The  animal  grows  very  weak,  the  appetite  capricious, 
lactation  ceases,  the  hair  coat  is  dull  and  erect,  the  eyes 
sunken,  the  body  thin  and  wasted. 

^  Diagnosis.-As  the  symptoms  are  not  especially  character- 
istic, in  the  absence  of  a  necropsy  the  diagnosis  is  difficult. 
The  microscopic  examination  of  the  feces  and  scrapings 
from  the  wall  of  the  rectum  for  the  specific  bacillus  is  helphil 
but  not  verv  reliable,  as  often  the  rectum  is  not  involved 
and  from  the  feces  usually  only  a  few  baci  li  can  be  obtained 
which  must  be  differentiated  from  tubercle  bacilli  and  non- 
pathogenic acid-fast  bacteria 

O.  Bang  recommends  testing  the  suspected  cattle  with 
tuberculin   prepared   from   avian   tubercle   bacilli.      Cattle 
affected  with  Johne's  disease  react  to  this  forni  of  tuberculin 
somewhat  as  do  tubercular  cattle  to  bovine  tuberculin,     ihe 
postinfection  temperatures  may  reach  as  high  as  l^o-^    i  • 
As  a  rule,  however,  the  postinjection  temperatures  are  lower 
than  in  tuberculosis.    Often  associated  with  the  rise  m  teni- 
perature   occur   constitutional   disturbances,   such   as   chill, 
diarrhea,  etc.    While  tubercular  cattle  react  to  avian  tuber- 
culin, those  affected  with  Johne's  disease  do  not  react  to 
bovine  tuberculin.    It  is  recommendable,  tWore    to  em- 
ploy   both    tuberculins   in    suspected    cases   that    tubercu- 
losis be   excluded.      By   thus   testing   a.id   destroying   the 
reactors  the  disease  has  been  eradicated  from  a  few  herds  in 
England. 


412  CIIROMC  JNFECriOVS  DISEASES 

Course,  'i'lie  course  is  prolonged,  exteiuliii<i;  over  se\eral 
niontlis.  It  seems  to  be  favorably  influenced  by  an  open-air 
life,  ])ut  close  confinement,  aihanced  preijnancy,  and  ])ar- 
turition  affect  the  course  adxersely. 

Prognosis. — The  projjnosis  is  bad.  Cases  which  may  be 
reco<i;nized  clinically  die  in  a  fcAV  weeks  to  a  few  months. 

Treatment. — No  successful  treatment  has  yet  been  devised. 
The  destruction  of  the  diseased  animals  j)revents  further 
spread. 

CASEOUS  LYMPHADENITIS  OF  SHEEP. 

Cheesy  Bronchopneumonia  of  Sheep.     Pseudo- 
tuberculosis OF  Sheep. 

Definition. — Caseous  Iym})hadenitis  is  an  infectious  disease, 
due  to  a  specific  bacillus,  which  sometimes  manifests  itself 
as  a  subacute  or  chronic  bronchojineumonia  and  at  other 
times  occurs  as  an  affection  of  the  sui)erficial  lymj)h  fjlands. 

Occurrence. — The  disease  appears  in  the  form  of  an 
epizootic  in  the  western  part  of  the  I  nited  States,  where  it 
induces,  especiall>'  anionij;  lambs,  a  large  mortality,  over  two- 
thirds  of  the  lambs  dying  of  the  disease.  It  therefore  attains 
economic  im])ortance.  The  disease  is  not  uncommon  in 
Europe,  Australia,  and  in  the  Argentine  Republic. 

Etiology. — The  cause  is  the  Bacillus  pseudotuberculosis 
ovis,  a  non-spore-bearing,  immotile  rod  which  may  be  easily 
stained  with  anilin  dyes.  It  also  stains,  according  to  (iram. 
The  germ  is  ])athogenic  to  swine,  guinea-])igs.  and  rabbits. 
Pigeons  and  fowls  are  not  very  susceptible. 

Natural  Infection. — Infection  })r()bably  takes  place  through 
the  digesti\e  tract,  although  it  may  enter  through  wounds 
(docking,  castration),  or  the  unshrivcled  navel  of  young 
calves.  The  droppings  of  infected  sheep  contain  the  bacillus 
in  large  numbers,  and  therefore  form  an  important  factor 
in  spreading  tiie  disease. 

Necropsy.  The  i)rin('i])al  lesions  are  found  in  the  lungs, 
lymph  glands  of  the  thorax,  and  the  external  lymph  glands. 
Throughout  the  lung  tissue  numerous  small,  gray  or  grayish- 
green   nodules  occur  which   through   coalescence  ma\'  form 


ACTINOM  YCOSIS-LUMF  J  A  W  "il  ^^ 

larc^e  cheesv  areas.  There  is  frequently  also  present  an 
adhesive  pleuritis.  The  corresponding  b^nph  f^f^^^]^ 
be  intact.  In  many  cases  the  lesions  are  confined  to  the 
e^teitlVph  glands,  which  are  enlarged,  and  whc^n^^^^ 
show  crreenish-vellow,  sticky,  smeary,  cheesy  masses  otten 
a^ged  in  concentric  layers  and  surrounded  by  a  capsule 
o  com  ective  tissue.  Often  the  caseous  mass  undergoes 
partTa   ca^^^^^^^^  changing  it  to  a  grayish- white,  gypsum- 

fike  mass.  In  rarer  instances  the  abc-m.a  organs^  are 
involved,  especially  the  liver,  spleen  and  kidneys  and  more 
rarelv  the  mesenteric  lymph  glands. 

Symptoms.-The  symptoms  are  rather  vague  M  t 
cases  are  discovered  in  the  slaughter  house.  Where  the 
afetion  involves  superficial  h^iph  glands,  tumors  appear 
on' he  s^u-f ace  of  the  body,  most  frequently  ui  the  prescapular 
Z^r^crnrsl  regions.  They  are  about  the  -e  of  -  ave^^^^ 
potato  and  are  not  sensitive  on  Palpatiom  The  condit  on 
of  the  sheep  otherwise  may  be  normal  except  that  the 
enlarged  Ivmph  glands  may  interfere  with  locomotion. 

When  the  lungs  are  affected  the  patient  shows  cough 
d  Jpnea,  temia,%maciation,  and  ultimately  cachexia  and 

'^'course  and  Prognosis.-The  course  is  prolonged,  the  disease 
laS'teek!  or  months  with  a  gradual  wastmg  of  the 
paW  The  mortality  varies  but  may  reach,  especialh 
among  lambs,  as  high  as  70  per  cent 

Treatment.-Medicinal  treatment  is  of  no  avail.  The 
diseaTe  mav  be  prevented  to  a  certain  extent  by  a  thorough 
d  X^  of  \he  navel  immediately  a  ter  birth  and  of 
wounds  surgical  and  accidental.  Vaccmation  has  been 
rrceSullv  practised,  using  an  attenuated  strain  o  the 
bacSus  When  feasible  the  infected  droppings  should  be 
rendered  innoxious  by  disinfection  or  removal  to  fields  not 
used  for  sheep. 

ACTINOMYCOSIS.     LUMP  JAW. 

Definition.-Actinomycosis  is  an  infectious  disease  due  to 
a  s^eX  fungus  and  characterized  clinically  by  the  appear- 


414  CHRONIC  INFECTIOUS  DISEASES 

ance  of  either  connective-tissue  enlargements,  bone  growths, 
or  abscesses  which  usually  occur  about  the  head  of  the  animal 
afi'ected.    The  disease  is  not  contagious. 

Occurrence. — While  most  common  among  cattle,  actino- 
mycosis occurs  occasionally  in  swine  and  rarelx'  in  horses. 
Cattle  which  have  access  to  straw  stacks,  especially  of 
barley  or  bearded  wheat,  are  most  often  attacked.  It  may 
happen  that  a  whole  herd  of  :iteers  or  heifers  running  about 
a  straw  stack,  which  serves  them  for  shelter  and  in  part 
food,  will  become  victims.  Stable-fed  cattle  are  often 
infected  by  forage  fed  in  a  dry  state,  but  which  was  grown 
on  lowlands  subject  to  overflow.  While  clinicall\'  the  disease 
is  more  important  to  the  surgeon  than  to  the  internist, 
it  not  infrequently  affects  internal  organs  (lungs,  liver, 
stomach),  and  leads  to  the  condemnation  of  the  carcass  in 
the  abattoir. 

Etiology. — ^The  cause  of  the  infection  is  a  thread-like 
fungus  known  as  the  Streptothrix  actinomyces  or  the  Actino- 
myces bovis.  A  common  name  for  it  is  the  ray  fungus. 
This  fungus  grows  on  various  kinds  of  grasses,  but  particu- 
larly on  the  awns  and  glumes  of  barley  and  related  grasses, 
especially  when  these  have  grown  on  bottom  lands  subject 
to  o^'erf^()v^■. 

Natural  Infection. — Infection  takes  place  through  the 
nnicous  membrane,  usually  of  the  mouth,  or  through  wounds 
in  the  skin.  Forage  infested  with  the  fungus,  provided  it 
contains  sharp  awns  or  glumes  or  the  sharp  cut  ends  of 
coarse  straw  (stubble),  easily  cuts  the  mucous  membrane, 
introducing  the  fungus  into  the  wound  at  the  same  time, 
("attle  from  the  Southwest  suffer  from  eating  cactus,  the 
sharp  spines  of  which  wound  the  mouth.  ObA-iously  when  the 
mucous  membrane  of  the  mouth  is  edematous  and  tender  as 
occurs  when  the  deciduous  teeth  are  being  shed  the  op- 
j)()rtunity  for  infection  is  greatest.  Sometimes  the  infection 
enters  the  alveolus  of  a  tooth,  leading  to  the  development  of 
disease  of  the  bone  of  the  jaw  (periostitis,  osteitis,  osteomye- 
litis). If  the  mucosa  of  the  cheek  is  infected  either  abscesses 
(young  animals)  or  connective-tissue  growths  ap])car  about 
the  head.    If  the  tongue  is  invaded  either  a  diH'use  connective- 


ACTINOMYCOSIS— LUMP  JAW  415 

tissue  proliferation  follows  or  multiple  circumscribed  actino- 
mycotic foci  result.  In  swine  sharp-pointed  plant  particles 
may  enter  the  crypts  of  the  tonsils  and  set  up  infection. 
Otherwise  swine  are  most  commonly  infected  through  skin 
wounds.  Sows  with  pendent  udders  pasturing  on  stubble 
fields  often  suffer  from  udder  actinomycosis,  and  pigs  are 
infected  through  castration  wounds,  especially  if  allowed 
access  to  straw  stacks.  The  infection  of  internal  organs  may 
be  primary  or  secondary.  Actinomycosis  may  involve  the 
udder,  spermatic  cord  of  castrated  animals,  vagina  and  via 
metastasis  the  liver,  spleen,  muscle,  and  brain.  A  generaliza- 
tion of  the  process  is,  however,  rare. 

Symptoms. — Cattle. — Actinomycosis  in  cattle  usually 
appears  in  one  of  the  following  forms:  (a)  Enlargements 
about  the  head,  particularly  in  the  neighborhood  of  the 
lower  jaw  (angle  and  .between  rami)  and  in  the  parotid 
region — the  so-called  actinomycoma.  (6)  An  affection  of  the 
tongue,  (c)  Disease  of  the  lips,  {d)  In  the  form  of  growths 
in  the  mouth,  pharynx,  and  larynx. 

(a)  In  young  cattle  the  enlargement  may  appear  as  an 
abscess  which  when  evacuated  is  found  to  contain,  mingled 
with  the  pus,  numbers  of  pale  or  sulphur-yellow-colored 
granules  (fungi).  Such  an  enlargement  presents  the  char- 
acterists  of  a  subacute  abscess.  The  connective-tissue 
growths  are  firm,  non-sensitive,  movable,  the  overlying  skin 
partially  adherent;  their  development  is  slow.  In  time 
they  undergo  puriform  softening  and  perforate  at  one  or 
more  points.  Out  of  the  sinuses  is  discharged  a  viscid, 
mucopurulent  exudate.  If  the  bone  is  involved,  the  infection 
leads  to  periostitis,  rarefying  osteitis  and  osteomyelitis. 
The  enlargement  is  hard,  non-movable  somewhat  sensitive 
and  usually  involves  one  or  more  of  the  premolar  teeth;  it 
also  tends  to  perforate.  At  first  several  openings  appear 
which  later  merge  into  one  large  crater-like  cavity  from  which 
issues  a  foul-smelling  discolored  discharge. 

(6)  If  the  tongue  is  seriously  involved  prehension  and 
mastication  are  interfered  with.  It  will  be  noted  in  the 
earlier  stages  that  the  patient  does  not  lick  the  corners  of 
the  manger  or  feed-box  clean,  as  the  tongue  is  stiff"  and 


41G  CHRONIC  INFECTIOUS  DISEASES 

caiiuot  he  protnidrd  sufficiently.  There  is  iiiort'  or  less 
ptyalisin  and  a  gradual  decline  in  the  condition  of  the  animal 
is  observed.  If  proper  treatment  is  not  given  the  animal 
may  become  reduced  to  a  skeleton.  On  opening  the  mouth 
the  changes  seen  in  the  tongue  will  deiXMid  upon  whetiier  the 
organ  is  diH'usely  infiltrated  or  the  process  confined  to  iso- 
lated areas.  In  the  former  case  the  tongue  appears  larger 
than  normal,  is  stiff',  moved  very  little,  and  feels  firm  or 
hard.  "The  organ  may  become  entirely  useless  to  the  animal 
(so-called  'Svooden  tongue").  In  the  second  case  throughout 
the  tongue,  especially  along  the  dorsum,  nodules  from  the 
size  of  a  shoe-button  to  a  hickory-nut  are  felt.  Occasionally 
ulceration  ap])ears  and  usually  just  in  front  of  the  dorsal 
prominence  of  the  tongue.  Surrounding  the  ulcer  cavity 
polypoid  growths  are  often  noted.  The  ulcer  may  be  covered 
with  accumulations  of  food,  hairs,  etc.,  and  obscured  from 
view. 

(c)  Actinomycosis  of  the  lips,  while  common  in  some 
parts  of  Europe,  is  rare  in  this  country.  As  with  the  tongue 
there  occurs  a  proliferation  of  the  connective  tissue,  especially 
of  the  upper  lip,  which  becomes  firm  and  rigid  and  greatly 
increased  in  size.  In  other  cases  multiple  nodules  from  the 
size  of  a  pea  to  a  wahnit  api)ear  in  the  coiuiective  tissue 
of  the  lip. 

(f/)  Actinomycosis  of  the  pharynx  leads  to  severe  dyspnea, 
dysphagia  and  swelling  in  the  subparotid  region,  which  in 
some  cases  is  quite  marked.  The  pharyngeal  enlargement 
may  l)e  ])alpated  from  without  (head  extended)  or  through 
the  mouth.  In  calves  firm  growths  the  size  of  a  fist  may  be 
palpated  in  the  thyroid  region.  They  ]>roduce  dys])hagia, 
dyspnea  with  wheezy  respirations,  and  general  unthriftiness; 
marked  rales  may  be  heard  on  auscultation  over  the  throat. 

Diagnosis. — The  diagnosis  of  actinomycosis  depends  u])on 
hiiding  of  the  ray  fungus  under  the  microscope.  The 
lesions  described  are  suggestive.  Swellings  due  to  injury 
might  be  confused  with  actinomycomas.  IIowe\'er,  these 
api)ear  suddenly,  show  an  infianunatory  character  and  a 
benign  course.  OccasionallN'  foreign  liodies  (bones,  shoe 
soles)  may  lodge  between  the  teeth  and  the  cheeks,  causing 


GLAXDERS— MALLEUS  417 

a  protrusit)!!  of  the  latter  which  resembles  slightly  an  actino- 
mycoma.  Actinomycosis  of  the  larynx  or  pharynx  liiight  be 
easily  confused  with  tuberculosis.  However,  the  affection  of 
the  corresponding  lymph  glands  which  occurs  in  the  latter 
and  rarely,  if  ever,  in  the  former  and  the  use  of  the  tuberculin 
test  should  suffice  for  dift'erentiation. 

Course  and  Prognosis. — The  course  in  actinomycosis  is 
chronic,  the  disease  gradually  progressing  from  month  to 
month  until  it  terminates  fatally.  A  few  cases  which  are 
mild  may  recover  spontaneously.  As  a  rule,  where  bone  is 
not  involved  and  the  location  of  the  lesion  permits  of  opera- 
tion, surgical  intervention  produces  a  cure;  or  if  taken  early 
and  the  lesion  is  internal  (tongue,  pharynx)  or  external 
healing  is  possible  through  the  use  of  iodin. 

Treatment. — Superficial  actinomycomas  are  treated  sur- 
gically by  extirpation  and  subsec[uent  cauterization  or  tinc- 
ture of  iodin  applied  to  the  wound.  Bone  enlargements 
are  usually  incurable.  Tongue  and  throat  lesions  and  in- 
operable actinomycomas  are  successfully  treated  with  iodin 
in  the  form  of  iodid  of  potash.  This  is  administered  in  doses 
of  '2k  drams  per  day  for  each  1000  pounds  animal.  Each 
dose  of  iodid  of  potash  is  dissolved  in  a  pint  of  water  and 
given  as  a  drench,  repeated  daily  for  ten  days  or  two  weeks 
or  until  symptoms  of  iodism  appear  (discharge  from  nose 
and  eyes,  peeling  off  of  superficial  layers  of  skin,  loss  of 
appetite).  The  use  of  the  drug  is  then  discontinued  until 
all  s^^llptoms  of  iodism  subside,  when  it  may  be  again  ad- 
ministered. It  usually  requires  from  three  to  foiu"  weeks  to 
produce  a  cure.  A  few  animals  show  no  reaction  to  the 
treatment.  These  had  best  be  slaughtered.  In  addition  it 
is  recommended  to  paint  the  tumors  with  tincture  of  iodin 
or  to  inject  into  them  Lugol's  solution.  With  the  iodin 
treatment  on  the  average  about  To  per  cent,  of  the  cases 
recover. 

GLANDERS.     MALLEUS. 

Definition. — Glanders    is    a    contagious,    usually    chronic 
infectious  disease  of  horses,  asses,  and  mules.     It  is  char- 
acterized by  the  formation  of  nodules  which  tend  to  degen- 
27 


418  CHRONIC  INFECTIOUS  DISEASES 

erate  ami  form  ulct^rs  in  the  mucous  membranes,  skin,  and 
internal  organs,  especially  the  lungs.  The  flisease  occasion- 
ally attacks  man  and  carnivorous  animals.  Sheep  and  goats 
may  be  inoculated  artificially. 

Occurrence. — Glanders  is  generally  distributed  throughout 
the  woi-Jd.  It  is  commonest  in  cities  or  on  the  ranges  where 
large  numbers  of  horses  are  congregated  together,  giving  it 
greater  opportunity  for  spread.  In  the  Inited  States  it  is 
especially  common  in  the  larger  cities,  and  has  occurred  on 
the  ranges  in  the  Northwest.  As  glanders  is  a  local  disease 
in  its  incipient  stages,  presenting  no  clinical  symptoms,  and 
usually  takes  a  chronic  course,  horse  .owners  and  persons 
ignorant  of  its  character  not  only  resist  efforts  to  eradicate 
the  disease  but  disregard  its  contagious  character.  It  is  not 
uncommon  in  the  United  States  to  find  glandered  horses 
housed,  fed,  watered,  and  even  worked  with  healthy  horses. 
Through  this  neglect  glanders  is  probably  more  wide-spread 
in  this  than  in  any  other  country  in  the  world.  Scandinavia 
and  Australia  are  free  from  it. 

Etiology. — Glanders  is  due  to  the  Bacillus  mallei,  a  straight 
or  slightly  curved,  aerobic  bacillus,  which  has  a  characteristic 
growth  on  potatoes  and  is  essentially  an  obligatory  parasite. 

Natural  Infection. — Susceptible  animals  are  infected  with 
glanders:  (a)  Through  the  digestive  tract  with  the  food  and 
water  which  has  been  contaminated  with  the  discharges 
(nasal,  farcy-bud)  or  more  rarely  with  manure  and  urine 
of  glandered  animals,  (b)  Through  skin  wounds.  Infection 
through  skin  wounds  is  very  rare.  It  may  follow  the  use  of 
an  infected  harness  which  rubs  and  chafes  the  skin,  (c) 
Through  the  respiratory  tract.  It  is  exceedingly  uncommon 
for  glanders  to  be  transmitted  in  this  way,  especially  if  the 
mucous  membranes  are  intact.  The  inhalation  of  the  moist 
spray  coughed  or  sneezed  out  by  a  glandered  patient  is  not  a 
common  occurrence;  in  the  dry  state  the  glanders  bacilli 
have  a  very  low  virulency.  At  any  rate,  primary  nasal  and 
lung  glanders  are  exceedingly  rare  forms,  (d)  By  the  act 
of  coitus.  Occasionally  instances  of  transmission  of  the 
disease  from  an  infected  stallion  to  a  mare  through  copulation 
are  recorded. 


GLANDERS— MALLEUS  419 

Glanders  is  nearly  always  introduced  into  a  stable  tlirough 
an  infected  individual,  usually  a  horse  suffering  from  chronic 
pulmonary  glanders,  and  which  shows  no  symptoms  of  either 
nasal  or  skin  glanders.  From  this  animal  it  usually  spreads 
to  the  ones  next  adjacent  or  sometimes  to  animals  farther 
removed  in  other  parts  of  the  stable.  When  the  horses  are 
permitted  to  drink  out  of  a  common  trough  or  fed  out  of  a 
common  crib,  the  infection  spreads  more  rapidly  than 
under  opposite  conditions.  It  is  a  notorious  fact  that  an 
apparenth-  sound  horse  may  infect  a  large  number  of  horses 
with  which  it  comes  in  direct  or  indirect  contact.  Dealers' 
stables  and  livery  barns  may  be  more  or  less  permanently 
infected.  Strange  horses  brought  there  to  be  fed  or  watered 
are  thus  exposed  to  the  infection.  Public  watering  troughs 
are  particularly  dangerous  in  this  regard.  The  horse  is  not 
as  susceptible  to  glanders  as  the  ass  or  the  mule.  In  fact, 
horses  offer  a  remarkable  resistance  to  infection,  the  disease 
in  them  usually  assuming  a  chronic  form,  and  sometimes 
ending  in  recovery.  In  asses  glanders  usually  takes  an  acute 
course  with  rapid  and  fatal  termination.  The  mule  in  this 
regard  seems  to  stand  between  the  two.  Obviously  anything 
which  will  reduce  the  resistance  of  the  horse,  such  as  over- 
work, poor  food,  exposure  to  weather,  etc.,  will  render 
the  animal  more  susceptible. 

Symptoms. — ^Following  natural  infection,  weeks  or  months 
may  elapse  before  clinical  symptoms  appear,  although  during 
this  time  the  patient  may  show  an  occasional  rise  in  tem- 
perature. In  not  a  few  instances  prominent  clinical  symptoms 
never  occur  during  the  life  of  the  patient. 

The  period  of  incubation  is  usually  placed  at  two  weeks. 

For  convenience  it  is  customary  to  classify  glanders  from  a 
clinical  standpoint  as:  (a)  Nasal  glanders;  (6)  skin  glanders ;i 
(c)  pulmonary  glanders.  In  this  connection  it  is  well  to  bear 
in  mind,  however,  that  any  two  or  all  three  of  these  forms 
may  be  combined.  Further,  it  is  very  rare  not  to  find  pul- 
monary glanders  present  either  alone  or  associated  with 
skin  and  nasal  lesions. 

1  Skin  glanders  was  formerly  known  as  farcy,  which  term  js  now  practi- 
cally obsolete. 


420  CHRONIC  INFECTIOUS  DISEASES 

Nasal  (flanders. — The  first  symptom  iK)te(l  is  usually 
nasal  discharge,  which  is  very  commonly  unilateral.  The 
cjuality  and  amount  of  the  discharge  vary  greatly.  In 
chronic  glanders  it  is  at  first  serous  or  mucoserous;  later  it 
becomes  more  copious,  quite  viscid,  and  often  mixed  with 
blood.  The  discharge  tends  to  adhere  to  the  wings  of  the 
nostrils  where  it  dries  to  form  brownish  crusts.  Coughing 
or  sneezing  momentarily  augments  the  discharge  which  is 
rarely  oflorous. 

The  nasal  mucosa  is  swollen,  of  a  leaden  hue,  and  the 
veins  much  distended.  If  low  enough  down  in  the  nasal 
cavity,  nodules  from  the  size  of  a  shot  to  a  pea  may  be  seen 
and  felt.  They  are  of  a  gray  or  yellow  color,  and  often 
surroiuided  by  a  red  zone.  These  nodules  soon  break  down, 
forming  ragged  ulcers  with  a  dirty  yellow  base.  By  confluence 
large  irregular  areas  of  ulceration  develop,  especially  on  the 
septum,  but  also  on  the  turbinals.  In  some  cases  the  whole 
mucosa  becomes  an  ulcerated  surface.  The  favorite  seats 
of  the  ulcers  are  the  septum  nasi,  turbinals,  and  the  nostril 
margins,  particularly  the  internal  surface  of  the  internal 
wing.  As  the  ulcers  age  their  walls  become  thickened, 
bolster-like,  and  the  base  paler.  Often  between  the  ulcers 
peculiar  stellate,  radiate  or  irregular  elongated,  elevated 
proliferations  of  connective  tissue  appear,  the  so-called 
"star-shaped  cicatrices."  Sometimes  they  are  not  associated 
with  ulcers,  the  latter  having  healed.  With  the  development 
of  the  cicatrices  and  the  disappearance  of  the  ulcers  the 
nasal  discharge  ceases.  Occasionally  an  ulcer  occurs  on  the 
apex  of  the  scar.  When  the  mucosa  is  much  thickened,  due 
to  the  chronic  indurative  inflannnation,  the  lumen  of  the 
nasal  passages  is  so  encroa<'hc<l  upon  that  i)ronounce(l  nasal 
inspiratory  dyspnea  with  wheezing,  blowing  sounds  is  heard 
on  exercise.  Ulceration  of  the  lower  pact  of  the  nose  may 
extend  to  the  skin  of  the  li])s,  which  becomes  swollen.  Nodules 
and  ulcers  may  a]>])car  in  the  swollen  area. 

The  submaxillary  lyini)h  glands  of  the  alVccted  side  are 
always  enlarged  in  nasal  glanders.  At  iirst  the  glands  are 
difi'usely  swollen,  somewhat  hot  and  tender,  but  later  they 
become  well  circumscribed,  painless,  and  nodular.     In  time 


GLANDERS— MALLEUS  421 

they  adhere  to  the  jaw,  the  skin  over  them  l)ecomnig  im- 
movable. With  the  eru})tion  of  fresh  nodes  or  uleers  in  the 
nose  the  submaxiUary  j^hinds  may  show  temporary  inflam- 
matory symptoms.  Spontaneous  rupture  of  the  swelhngs 
is  very  rare.  Occasional  conjuncti\'itis  and  keratitis  may 
accompany  nasal  glanders. 

Skin  Glanders. — In  skin  glanders  so-called  farcy  nodes 
(farcy-buds)  and  ulcers  (chancres)  occur  in  the  subcutaneous 
connecti\'e  tissue  and  skin.  The  nodes  vary  in  size  from  a 
])ea  to  a  walnut.  They  soon  break  down,  forming  ulcers. 
They  may  appear  without  infiltration  of  the  adjacent  con- 
nective tissue,  but  very  commonly  a  zone  of  reactive  inflam- 
mation surrounds  them.  The  ulcers  are  irregular  in  shape, 
with  ragged  edges  which  overhang  the  base.  The  base  of 
the  ulcer  is  usually  of  a  dirty  gray  color,  although  it  may  be 
covered  by  a  brownish  scab.  The  discharge  may  be  scant 
and  thin  or  more  copious  and  thick.  In  the  former  case  it 
has  an  oily  appearance  and  a  very  viscid  consistency.  In  the 
latter  a  thick  pus  is  discharged  which  does  not  adhere  readily 
to  the  hair.  While  the  ulcers  are  generally  indolent,  they  not 
infrequently  heal,  leaving  behind  small  scars  which  do  not 
entirely   become   covered   with   hair. 

The  lymph  vessels  in  the  neighborhood  of  the  nodes  and 
ulcers  are  frequently  swollen,  appearing  like  cords  or  ridges 
under  the  skin.  They  are  usually  hot  and  sensitive.  After 
remaining  for  a  time  they  may  gradually  disappear,  or  along 
their  course  ulcers  erupt.  The  superficial  lymph  glands 
(inguinal,  popliteal,  prepectoral)  may  become  swollen,  hot 
and  tender.     Later  they  are  hard  and  less  sensitive. 

In  chronic  skin  glanders  there  is  a  tendency  for  the  skin 
and  subcutis  of  one  or  more  limbs  (especially  the  hind  ones) 
to  undergo  fibrous  thickening  (elephantiasis)  which  ends 
abruptly  at  the  hoof.     Quite  often  the  patient  is  lame. 

Pulmonary  Glanders. — Nearly  every  case  of  glanders  begins 
in  the  lungs.  As  a  rule,  however,  the  earlier  symptoms  of 
pulmonary  glanders  are  so  vague  that  a  diagnosis  from 
physical  examination  alone  is  impossible  (so-called  "occult" 
glanders).  As  in  tuberculosis  of  the  ox,  months  may  elapse 
before  the  infected  patient  shows  clinical  evidence  of  the 


422  CHRONIC  INFECTIOUS  DISEASES 

disease.  In  tlie  meantime  a  nnnibcr  of  horses  may  become 
infected  l)y  the  unsuspected  "occult  case."  The  patient 
may  show  occasional  couu;!!,  which  is  usually  dull,  weak, 
and  dry.  Less  often  periodical  slight  nasal  hemorrhages 
(epistaxis)  are  noted.  The  horse  may  tire  easily  at  work  and 
show  dyspneic  symptoms  resembling  "heaves."  From  time 
to  time  the  temperature  may  be  elevated  1°  or  2°.  Percussion 
of  the  thorax  usually  gives  negative  results.  In  rare  cases 
dulness  from  an  area  of  the  lung  luay  be  determined,  which 
speaks  for  a  superhcially  located  glanders  tumefaction  at 
least  the  size  of  a  double  clenched  fist.  Auscultation  is 
usually  negative,  although  after  a  smart  gallop  moist  rales 
are  heard  in  some  cases,  especially  if  the  ear  is  placed  over 
the  lower  end  of  the  trachea,  'i'he  trachea  is  sensitive  on 
palpation  in  indi\'idual  instances  (tracheitis).  If  the  larynx 
is  involved,  spasmodic  cough  and  inspiratory  dyspnea  with 
stenotic  noise  are  noted.  As  a  rule,  in  time  the  general 
condition  of  the  patient  becomes  bad.  It  loses  weight,  the 
hair  coat  appears  dull,  and  the  mane  and  tail  hairs  become 
loose.  In  some  cases  there  is  a  tendency  for  passive  edemas 
to  develop  on  the  limbs  and  pendent  portions  of  the  body 
(sheath,  udder,  ventral  i)art  of  the  abdomen).  Following 
a  remission  in  the  course  of  the  disease  these  dropsical 
sym])toms  may  temporarily  disap])ear. 

Diagnosis. — Provided  the  clinical  symptoms  are  well 
developed  the  diagnosis  of  glanders  is  not  difficult.  The 
occurrence  of  the  nodules,  characteristic  ulcers,  and  stellate 
cicatrices  on  the  mucous  membrane  of  the  nasal  cavity, 
the  enlargement  of  the  submaxillary  lymph  glands,  and  the 
symptoms  of  fever  are  almost  pathognomonic.  However, 
in  many  cases  the  lesions  are  too  high  uj)  in  the  nasal 
cavity  (or  they  may  be  in  the  adjacent  sinuses)  to  be  seen 
or  felt.  In  these  cases,  unless  there  is  a  history  of  glanders 
infection,  or  other  horses  or  mules  on  the  premises  showing 
tyi)ical  lesions,  the  diagnosis  from  ordinary  ])hysical  (>xanuna- 
tion  may  be  impossible. 

The  skin  glanders  is  characterized  by  the  indolent  ulcers 
which  often  are  not  surrounded  by  a  zone  of  acute  inflam- 
mation.     However,    any    persistent    edematous    swelling, 


GLANDERS— MALLEUS  423 

nodular  thickening  or  ulcer  formation  on  any  part  of  the 
body,  especially  under  the  abdomen,  sheath  or  udder  should 
be  looked  upon  with  suspicion. 

Differential  Diagnosis. — There  are  a  number  of  diseases 
producing  nasal  discharge,  lesions  on  the  nasal  mucous 
membranes,  swellings  of  the  submaxillary  lymph  glands, 
and  nodules  and  ulcers  in  the  skin.  At  times  some  of  these 
appear  strikingly  like  glanders.  Formerly  when  a  differen- 
tiation was  only  possible  by  carefully  weighing  the  clinical 
phenomena  these  diseases  were  extremely  important  to 
consider.  However,  we  have  now  available  several  accurate 
methods  of  diagnosis  which  can  be  employed.  When  doubt 
exists  in  clinical  cases  or  when  there  is  no  clinical  evidence  of 
the  disease,  although  the  patient  has  been  exposed,  the 
following  methods  of  diagnosis  are  now  available. 

(a)  The  Mallein  Test. — Mallein  which  is  prepared  from 
the  glanders  bacillus,  much  as  tuberculin  is  prepared  from  the 
tubercle  bacillus,  when  properly  used,  is  a  reliable  test  for 
glanders.  It  may  be  instilled  into  the  eyelid  (ophthalmic 
reaction)  or  applied  subcutaneously  (hypodermic)  or  rubbed 
into  a  disinfected  area  of  the  scarified  skin  (endermic).  The 
ophthalmic  method  is  now  most  generally  employed  and 
seems  to  be  the  most  accurate  of  the  three. 

The  ophthalmic  method  of  using  mallein  is  quite  simple. 
It  consists  in  dropping  into  one  of  the  eyes  of  the  animal  to 
be  tested  3  to  5  drops  of  concentrated  mallein,  or  the  mallein 
may  be  introduced  into  the  conjunctival  sac  with  a  camel- 
hair  brush.  The  reaction  usually  begins  five  or  six  hours 
after  the  instillation  of  the  mallein  and  lasts  from  twenty-four 
to  thirty-six  hours.  A  positive  reaction  is  manifested  by  an 
accumulation  of  yellow  exudate  at  the  inner  canthus  of  the 
eye  to  which  the  mallein  has  been  applied.  In  some  cases 
the  discharge  is  very  slight,  in  others  profuse  and  usually 
associated  with  severe  conjunctivitis;  at  other  times  the 
conjunctivitis  is  absent.  The  intensity  of  the  reaction  is  not 
an  index  of  the  extent  of  the  disease.  Ordinary  mallein 
used  for  subcutaneous  testing  is  not  adaptable.  The  Bureau 
of  Animal  Industry  prepares  a  special  mallein  for  ophthalmic 
tests,  which  contains  no  glycerin  as  a  preservative.     Some 


424  CHRONIC  rXFECTinCS  DISEASES 

expi'i-iiiK'nters  have  used  dry  mallein  (inallein  sicciini).  As  a 
rule  positive  reactions  are  not  attended  by  fe\er  or  systemic 
disturbances.  Some  <i;landere(l  horses,  however,  are  so 
hypersensitive  to  mallein  that  they  <jive  a  thermic  reaction. 
It  is  therefore  a(hisable  to  take  the  temperature  just  before 
the  mallein  is  instilled  and  again  when  the  exe  is  being 
examined  to  determine  the  reaction.  When  the  reaction  is 
doubtful  the  complement-fixation  test  may  be  used  as  a 
control.  The  test  may  be  repeated  within  twenty-four  ht)urs 
on  the  same  or  control  eye.  If  another  retest  is  necessary 
it  should  not  be  made  in  less  than  three  weeks. 
The  subcutaneous  method  is  a})plied  as  follows: 

1.  The  normal  rectal  temperatures  of  the  horse  to  be 
tested  are  first  determined  one  or  two  days  before  the  injec- 
tion of  mallein  is  made,  best  taking  them  each  morning, 
noon,  and  evening. 

2.  The  mallein  is  injected  in  doses  of  1  c.c.  into  the  side 
of  the  neck. 

o.  Beginning  four  ito  eight  hours  after  the  injection,  the 
postinjection  temperatures  are  obtained  every  two  hours 
until  the  twentieth  hour  after  injection,  and  carefully 
recorded. 

Ititcrpretdtioii  of  J{rsiilt,s. — A  typical  reaction  consists  in 
an  elevation  of  temperature  of  at  least  .3.()°  F.,  and  must 
exceed  104°  F.  The  temperature  curve  usually  remains  at  an 
elevation  for  some  time,  or  it  may  take  a  slight  drop  and 
rise  again  later  in  the  day.  Such  a  reaction  is  spoken  of  as 
positive.  On  the  second  and  sometimes  on  the  third  da\' 
a  second  temperature  curve,  though  usually  less  pronounced, 
may  occur. 

When  the  i)ostinjection  tcmj)crature  exceeds  the  highest 
preinjection  temi)crature  2.7°  F.  and  reaches  1(K>.1°  F. 
or  over,  aud  a  marked  swelling  occurs  at  the  point  of 
inoculation,  the  swelling  being  hot,  sensitive  and  at  least 
o  to  10  cm.  in  diameter  the  reaction  is  positive.  The  swelling 
should  persist  for  at  least  twenty-four  to  thirty  hours. 

The  reaction  is  doubtful  even  if  the  temperature  exceeds 
3.(5°  F.  and  no  local  reaction  appears. 

The  reaction  is  negative  when,  notwithstandiug  the  height 


GLANDERS— MALLEUS  425 

that  the  temperature  may  reach,  tlie  fel)rile  condition  does 
not  last  at  least  four  to  six  hours. 

The  reaction  is  negative  when  the  temperature  elevation 
is  not  more  than  1.8°  F.  and  does  not  exceed  102.5°  F. 

A  positive  reaction  denotes  that  the  jjatient  is  affected 
with  glanders.  An  atypical  reaction  indicates  that  the  case 
should  be  considered  suspicious.  A  negative  reaction  denotes 
the  absence  of  glanders.  Cases  of  doubtful  reaction  should 
be  retested  but  not  sooner  than  fifteen  days  to  six  weeks 
following  the  next  previous  test. 

(b)  Serum  Diagnosis  by  Means  of  Agglutination. — ^The 
so-called  agglutination  test  for  glanders  is  a  fairly  reliable 
laboratory  method  in  which  the  serum  of  the  blood  of  a 
suspected  horse  is  prepared  in  various  dilutions  by  means  of 
the  addition  of  physiological  salt  solution.  In  order  to 
determine  the  agglutinating  power  equal  quantities  of  emul- 
sions of  glanders  bacilli  which  have  been  attenuated  by  heat- 
ing at  60°  C.  (test  fluid)  are  added  to  the  serum  solutions. 
Blood  serum  which  will  agglutinate  glanders  bacilli  in  dilu- 
tions 1  to  1000  or  in  greater  dilutions  must  be  considered 
as  coming  from  a  glandered  horse.  Agglutinations  occurring 
only  in  dilutions  ranging  from  1  to  500  to  1000  are  doubtful. 
Agglutinations  in  dilutions  of  less  than  500  indicate  the 
absence  of  glanders.  The  test  often  fails  in  chronic  glanders, 
the  serum  in  such  cases  having  a  very  low  agglutinating 
power.  On  the  other  hand,  some  healthy  horses  possess  an 
agglutinating  power  as  high  as  that  found  in  some  glandered 
horses.  Healthy  horses  recently  malleinized  (within  three 
months)  may  gi\-e  a  positive  agglutination  reaction. 

Since  it  is  the  degree  of  agglutination  and  not  agglutination 
itself  that  determines  whether  or  not  infection  is  present, 
misinterpretations  are  unavoidable.  When  the  agglutination 
test  is  to  be  employed  the  veterinarian  usually  only  collects 
the  serum  under  ])roper  precautions  and  sends  it  to  ex- 
perienced laboratory  men. 

(c)  Serum  Diagnosis  by  Means  of  Complement-fixation. — 
This  is  a  laboratory  method  for  the  diagnosis  of  glanders 
which  seems  to  be  very  accurate.  Practically  it  is  the 
application  to  glanders  of  the  ^Yassermann  test  for  s^-philis 


426  CHRONIC  INFECTIOUS  DISEASES 

in  man.  The  test  should  be  nuidc  by  an  exjjerienced  manipu- 
lator in  a  properly  equipped  laboratory.  The  practitioner 
usually  only  collects  the  serum  as  in  the  agglutination  test. 
The  results  so  far  obtained  from  this  method  are  very 
encouraging  (for  details  see  Bacteriology). 

(d)  Inoculation  of  E.rperhnenial  Animals. — For  this  pur- 
pose a  young  male  guinea-pig  is  chosen  which  is  inocu- 
lated intraperitoneally  with  an  emulsion  in  sterile  water 
of  nasal  or  skin  ulcer  discharge  from  a  suspicious  case. 
One  or  2  c.c.  are  injected  into  the  abdominal  cavity  of  the 
guinea-pig.  If  the  bacilli  of  glanders  are  present,  swelling 
of  the  scrotum,  followed  by  adhesion  of  the  testicles,  will 
occur  in  two  or  three  days.  Sometimes  only  a  skin  abscess 
at  the  point  of  inoculation  appears.  The  danger  of  general 
septicemia  may  be  avoided  by  keeping  the  material  in  a 
refrigerator  for  a  few  days  before  inoculation.  Potato 
cultures  should  always  be  made  from  the  lesions  in  the 
scrotum.  On  potato  the  true  glanders  bacilli  produces  yellow 
colonies  resembling  honey,  while  the  pseudoglanders  bacillus 
produces  white  colonies.  Positive  evidence  obtained  from 
this  method  is,  of  course,  much  more  valuable  than  negative. 
Occasionally  the  discharge  collected,  even  though  it  comes 
from  a  glandered  animal,  may  not  contain  glanders  bacilli. 
The  agglutination  and  complement-fixation  tests  have  largely 
superseded  this  method. 

Course. — The  course  in  glanders  is  xavy  varied.  Like 
tuberculosis  of  the  ox  its  duration  is  usually  a  matter  of 
months  or  years.  The  clironic  course  may  be  interrupted 
by  acute  exacerbations  and  remissions,  until  finally  the 
disease  assumes  a  clinical  form  in  which  either  nasal  or  skin 
glanders  or  both  become  manifest.  The  })atient  either 
dies  or  is  destroyed.  In  rare  instances  death  may  result 
from  inanition  or  occur  suddenly  following  pulmonary 
hemorrhage.  The  ])eriods  of  fever  which  occur  during  the 
course  of  the  chronic  disease  are  probably  due  to  the  de^•elop- 
ment  of  fresh  foci. 

To  a  certain  extent  the  course  depends  upon  the  food  and 
care  which  is  given  the  patient.  Poorly  fed,  overworked 
horses  more  readilv  succumb  to  the  disease.     The  nasal 


EPIZOOTIC  LYMPHANGITIS  427 

discharge  which  becomes  mixed  with  the  food  and  water  and 
is'  ingested  by  the  patient  produces  continual  reinfection, 
which  increases  the  development  of  the  disease. 

A  few  cases  of  pulmonary  glanders  and  even  nasal  and  skin 
glanders  recover.  Such  instances,  however,  are  exceptional 
in  temperate  climates.  It  is  said  that  in  tropical  countries 
glanders  sometimes  assumes  a  more  benign  form,  and  that 
])atients  showing  marked  clinical  s^Taptoms  of  the  disease 
ultimately  recover.  Similar  observations  have  been  made  in 
the  western  United  States.  They  belong  to  the  exceptional 
rather  than  the  rule. 

EPIZOOTIC  LYMPHANGITIS. 

Japanese  Farcy.    Saccharomycosis. 

Definition. — Epizootic  hmphangitis  is  a  chronic,  com- 
municable disease  of  solipeds  which  manifests  itself  as  a 
suppurative  inflammation  of  the  subcutaneous  l\Tnph  vessels 
and  regionary  lymph  glands. 

Occurrence. — The  disease  occurs  in  southern  Europe, 
but  has  also  been  reported  from  Finland,  Russia,  and 
England.  It  is  common  in  Asia  (Japan,  India)  and  Africa. 
Whether  or  not  true  cases  have  occurred  in  the  United 
States  is  problematical.  The  ones  so  diagnosed  are  probably 
"sporotrichosis"  presenting  similar  symptoms. 

Etiology. — ^The  cause  is  supposed  to  be  the  Cr^ptococcus 
farciminosus,  large  oval  bodies  very  difficult  to  stain,  found 
in  the  discharge  from  ulcers.  In  the  cases  which  occurred 
in  Pennsylvania  bacteriological  investigations  failed  to  reveal 
the  cr^'jjtococcus  but  did  show  the  presence  of  a  sporothrix 
identical  with  that  isolated  from  man.  Evidently  the 
Pennsylvania  outbreak,  and  very  probably  the  other  out- 
breaks in  this  country,  were  not  identical  with  the  epizootic 
l\inphangitis  first  described  by  Tokishiga  (1896)  and  Pallin 
(1904)  in  horses  in  Japan  and  India. 

Natural  Infection. — Evidently  occurs  through  small  lesions 
in  the  skin.  The  cr\'ptococcus  is  probably  carried  by  inter- 
mediate agents  such  as  harness,  bedding,   stable  utensils, 


428  CHRONIC  INFECTIOUS  DISEASES 

etc.  It  is  also  possible  that  insects  imiy  he  carriers  of  the 
infection.  The  disease  is  most  common  in  cold,  damp 
weather.  Asses  and  mnles  seem  more  predisposed  than 
horses.     Cattle  are  very   rarely   affected. 

Symptoms. — The  disease  usually  first  attacks  the  limbs, 
particularly  the  forelimbs,  but  may  also  occur  on  the  scrotum 
or  udder,  or  more  rarely  the  body  and  neck.  I'sually  the 
disorder  originates  in  a  wound  or  fresh  cicatrix.  A  wound  so 
infected  does  not  heal  but  is  converted  into  an  ulcer  with 
exuberant  granulations.  From  a  cicatrix  a  painful  nodule 
the  size  of  a  pigeon's  egg  forms,  which  later  erupts,  discharg- 
ing a  thick,  yellow  pus.  Soon  the  inflammation  involves 
the  lymph  vessels,  which  become  swollen,  corded,  and  very 
painful,  and  along  their  course  fresh  abscesses  develop. 
The  abscesses  rupture,  forming  ulcers  which  heal  slowly. 
The  ulcers  show  a  tendency  to  exuberant  granulation,  and 
by  confluence  are  spread  and  may  i)roduce  great  ulcerous 
surfaces.  The  regionary  lymph  glands  are  involved  in  the 
process;  not  infrequently  abscesses  form  in  them.  As  a 
rule  the  infected  limbs  swell;  particularly  about  the  joints 
and  in  the  overlying  skin  sui)erficial  ulcers  de\'elop. 

In  rare  instances  the  morbid  process  may  in\'ol\'e  the 
nasal  mucous  membrane,  on  which  form  white  nodules  and 
later  ulcers  which  tend  to  coalesce.  The  submaxillary  lymph 
glands  are  involved  and  may  suppurate.  Nasal  discharge 
is  rare.    Usually  the  appetite  and  teiuperature  remain  normal. 

Diagnosis. — The  disease  closely  resembles  skin  glanders, 
especially  chronic  cases.  In  doul)tful  instances  the  usual 
tests  for  glanders  may  be  applied.  Otherwise  a  microscopic 
examination  of  the  pus  from  a  true  case  of  epizootic  lymphan- 
gitis will  show  the  characteristic  parasites.  Tlcerous  lym- 
phangitis takes  a  nuich  mikler  course  and  the  pus  contains 
the  characteristic  bacillus. 

Course. — The  course  is  chronic.  Mild  cases  last  one  or 
two  months.  Remissions  and  exacerbations  are  not 
unconuuon.  The  mortality  varies  from  7  to  10  per  cent. 
Patients  which  recover  are  usually  left  with  thick  legs. 

Treatment. — The  treatment  is  largely  surgical  (extirpation 
of  tlu>  nodules,  early  opening  of  abscesses,  antiseptic  treat- 


ULCEROUS  LYMPHANGl^riS  OF   THE  HORSE      429 

ment  of  ulcers).    Iodic!  of  potash  improved  but  did  not  cure 
the  coiKhtion. 

Prophylaxis. — Prevention  consists  in  separating  the  sick 
from  the  healthy,  and  a  thorough  disinfection  of  the 
premises. 


ULCEROUS  LYMPHANGITIS  OF  THE  HORSE. 

Definition. — I'lcerous  lymphangitis  is  a  chronic,  infectious 
disease  of  horses  characterized  by  a  progressive,  suppurative 
inflammation  of  the  subcutaneous  lymph  vessels  along  the 
course  of  which  there  form  ulcers.  The  regionary  l^^nph 
glands  are  not  involved. 

Occurrence. — The  disease  was  first  described  by  Nocard  in 
France.  No  outbreaks  have  been  reported  in  the  United 
States.  A  similar  disease  has  been  observed  in  the  Philippine 
Islands. 

Etiology. — The  disease  is  due  to  a  bacillus  resembling  the 
bacillus  of  caseous  lymphadenitis  of  sheep. 

Natural  Infection. — The  bacillus  evidently  enters  through 
small  wounds,  particularly  in  the  skin  of  the  legs.  The 
disease  is  not  communicable. 

Symptoms. — The  first  symptom  noted  is  a  diffuse  swelling 
of  the  hindlimlis.  In  the  swollen  limb  develop  circumscribed, 
painful  nodules  which  undergo  puriform  softening,  forming 
ulcers  with  thin  borders  from  which  is  discharged  at  first  a 
creamy,  later  a  thinner  pus.  The  ulcers  tend  to  heal  readily, 
especially  if  antiseptics  have  been  applied  to  them.  Usually 
following  the  healing  of  the  first  ulcers  a  new  crop  of  nodules 
and  ulcers  form  between  which  the  lymph  vessels  swell 
to  strands  the  thickness  of  a  finger.  Along  the  course  of 
these  swollen  lymph  vessels  new  nodules  and  ulcers  con- 
tinually develop.  In  this  manner  the  disorder  may  continue 
for  several  months.  In  rare  cases  the  forelimbs,  body,  neck 
and  even  the  head  may  be  attacked,  leading  to  the  death  of 
the  patient.  In  some  instances  the  disease  takes  a  chronic 
course,  the  nodules  and  ulcers  appearing  in  the  winter,  heal 
during  the  summer  months,  to  reoccur  again  the  following 


430  CHRONIC  INFECTIOUS  DISEASES 

winter.  The  regionary  lyinj)h  glands,  while  swollen,  do  not 
take  part  in  the  suppuratixe  jjrocess. 

Diagnosis. — The  disease  resembles  in  some  respects  skin 
glanders.  There  are,  however,  differences  from  a  clinical 
standpoint.  The  ulcers  are  not  indolent  as  in  glanders  but 
heal  readily;  the  regionary  lymph  glands  are  not  involved; 
the  nasal  mucous  membrane  is  intact,  and  no  reaction  occurs 
to  mallein.  The  pus  from  the  nodides  and  ulcers  contains 
the  short  (iram-positixe  bacillus,  which  will  not  grow  on 
acid  potato.  In  guinea-pigs  a  very  rapidly  developing 
periorchitis  follows  intraperitoneal  injection,  the  purulent 
exudate  containing  the  characteristic  bacillus.  Compared 
with  epizootic  lymphangitis,  ulcerous  lymphangitis  is  a  mild 
disease.  In  the  former  the  roimd  or  o\al  cryptococci  are 
found  in  large  numbers.  The  disorder  resembles  contagious 
acne,  which,  however,  is  found  usually  only  where  the  saddle 
or  harness  comes  in  contact  with  the  skin. 

Treatment. — The  treatment  consists  in  washing  out  the 
ulcers  with  antiseptics.  If  the  process  tends  to  spread  the 
nodules  may  be  opened  and  disinfected.  Some  cases  resist 
treatment  obstinately.  Good  results  are  reported  from  the 
subcutaneous  injection  of  diphtheria  antitoxin  (50  c.c. 
daily). 

INFECTIOUS  ABORTION. 

Definition. — Infectious  abortion  is  a  specific  inflannnation 
of  the  mucous  membrane  of  the  uterus,  which  in  pregnant 
animals  leads  to  an  affection  of  the  fetal  membranes  and 
often  to  the  premature  birth  of  the  fetus. 

Occurrence. — Infectious  abortion  occurs  most  frequently 
among  cows  and  mares.  It  is  relatively  uncommon  in  ewes 
and  sows.  Among  cattle  it  is  widely  distributed,  forming 
one  of  the  commonest  infectious  diseases  with  which  we  have 
to  deal.  In  many  of  the  Eastern  States,  where  cattle  breeding 
is  extensively  carried  on,  fully  70  per  cent,  of  the  herds  are 
infected.  Among  mares  it  is  widely  distributed  but  olniously 
attracts  more  attention  in  breeding  studs  where  a  large 
numl)er  of  foals  are  lost  on  a  single  farm.  Isolated  cases 
may  escape  unnoticed.    The  disease  attains  economic  im- 


INFECTIOUS  ABORTION  431 

portance  not  only  because  it  leads  to  the  loss  of  a  number 
of  calves  or  foals  liut  also  in  cows  to  the  cases  of  sterility, 
retentions  of  afterbirth,  chronic  uterine  catarrhs,  and  diseases 
of  the  udder  which  follow  in  its  wake.  It  not  only  destroys 
the  young  but  may  greatly  lessen  the  value  of  or  even 
extirpate  the  dam. 

Etiology. — (a)  In  cows  the  disease  is  caused  by  the  Bacillus 
abortus.  This  is  a  -small,  non-motile,  non-spore-bearing 
bacillus  which  stains  irregularly  with  anilin  dyes  but  is  Gram- 
negative.  In  cultures  the  bacillus  is  originally  anaerobic  but 
gradually  assumes  aerobic  characteristics.  It  is  found  in  the 
uterine  exudate,  fetal  membranes,  and  in  the  fetus;  also  in 
the  udder  (milk)  of  infected  cows.  The  germ  is  highly 
resistant  and  may  remain  virulent  in  the  uterus  of  infected 
cows  for  several  months  after  they  have  aborted.  The 
disease  is  spread  primarily  by  the  uterine  discharge,  fetal 
membranes,  and  fetuses  of  infected  cows. 

(b)  The  abortion  of  mares  is  not  due  to  the  abortus 
bacillus  but  to  a  streptococcus  which  is  Gram-negative.  It 
is  found  in  the  uterus,  fetal  membranes,  and  fetuses  of 
infected  mares. 

Natural  Infection. — The  infection  is  taken  up  by  the 
susceptible  mother:  (o)  Through  the  digestive  tract,  the 
causal  germ  contaminating  the  food  and  water;  (b)  through 
the  genital  organs  which  may  become  infected  by  the  stable 
litter,  manure,  etc.,  or  by  contact  with  such  utensils  as 
buckets,  milking  stools,  ropes,  halters,  sponges,  douching 
hose,  obstetrical  instruments,  etc.  The  bull  may  also  be  a 
carrier  of  infection  as  he  can  transmit  by  coitus  the  bacilli 
which  have  collected  on  the  penis  during  copulation  with  an 
infected  female. 

Whether  the  bull  is  merely  a  mechanical  carrier  or  the 
abortus  bacillus  may  proliferate  in  the  genitalia  causing  him 
to  become  also  infected  and  therefore  a  permanent  distributor 
remains  undecided.  Experimentally,  abortion  has  been 
induced  in  pregnant  animals  by  introducing  pure  cultures 
of  the  abortus  bacillus  into  the  vagina,  stomach,  and  veins. 

The  disease  is  practically  always  brought  into  a  herd 
through  an  infected  female  which  has  either  recently  aborted 


4)52  CHRONIC  INFECTIOUS  DISEASES 

or  is  I'liininatiiifi  the  causal  fjjcrin  in  her  vaginal  discharge 
and  milk.  The  tendency  for  cattle  owners  to  dispose  of 
cows  which  have  aborted  insures  a  wide  dissemination  of  the 
disease.  In  rare  instances  the  premises  may  })ecome  infected 
through  a  contaminated  hull  to  which  the  cows  of  the  herd 
have  been  brought  for  service.  In  still  rarer  instances  a 
very  young  calf  from  an  infected  mother  may  introduce  the 
infection.  That  persons,  dogs,  fowls,  and  birds  of  the  air 
may  also  carry  infection  from  infected  to  non-infected 
premises  is  probable. 

Symptoms. — The  period  of  incubation  following  natural  or 
artificial  inoculation  is  varied.  It  averages  from  natural 
exposure  about  four  months  ('.]'.]  to  230  days).  Artificial 
transmission  of  vaginal  discharge  from  diseased  to  healthy 
cows  was  followed  by  abortion  in  9  to  21  days.  The  sjTnp- 
toms  which  indicate  the  presence  of  the  disease  in  a  cow 
herd  are:  (a)  A  number  of  cows  are  dropping  their  calves 
prematurely;  (h)  cows  which  have  aborted  show  an  abnormal 
vaginal  discharge,  and  (c)  the  api)earance  of  symptoms  of 
premature  labor,  especially  in  heifers. 

The  first  few  cases  of  abortion  in  a  herd  may  be  entirely 
overlooked,  as  they  are  apt  to  happen  during  the  first  weeks 
(five  to  seven)  of  ])rcgnanc\'  when  the  fetus  is  very  small. 
A  given  cow  may  thus  abort,  be  rebred,  conceive  and  abort 
again  without  the  owner's  attention  being  attracted  to  the 
condition.  Finally  after  aborting  twice  or  more  times  she 
may  carry  to  full  term  and  be  delivered  of  a  viable,  fully 
developed  calf.  Such  a  cow  is  spoken  of  as  an  "immune"  in 
the  sense  that  she  will  not  abort  again,  although  she  is  still 
diseased  and  can  infect  other  cows.  Abortion  seems  most 
common  in  the  fifth  to  sc^■cnth  months  of  pregnancy,  usually 
occurring  on  or  about  the  HlOth  day,  but  varying  from  the 
14<)tli  to  the  254th  day.  Quite  often  before  the  actual 
abortion  occurs  the  cow  shows  jH-odromal  symptoms  such  as 
filling  of  the  udder,  edema  of  the  vulva,  colostral  milk, 
sinking  on  each  side  of  the  tail-root,  congestion  of  the  \aginal 
mucosa  and  the  discharge  of  a  reddish  or  yellow  odorless, 
viscid  Huid.  The  exijulsion  of  the  uterine  contents  usually 
occurs,  h()wc\er,  without  marked  labor  ]iains  and  the  fetus 


INFECTIOUS  ABORTION  433 

comes  dead.  After  the  abortion  the  placenta  is  often  retained 
and  a  vaginal  discharge  persists.  For  two  or  three  we;^ks  or 
longer  the  discharge  is  of  a  dirty  reddish-brown  color,  odor- 
less or  odorous,  the  flow  either  continuous  or  interrupted. 
In  time  the  discharge  usually  diminishes.  When  bred  during 
this  period  the  cow  may  not  conceive.  It  occurs  occasionally 
that  cows,  especially  heifers,  may  show  all  of  the  premonitory 
symptoms  of  abortion,  fail  to  abort  and  carry  to  full  term. 

Necropsy. — On  postmortem  the  uterus  appears  externally 
normal.  Between  the  mucosa  and  the  chorion  is  found  an 
exudate  which  is  fluid  to  semisolid  and  of  light  brownish- 
yellow  color.  The  fetus  appears  normal.  In  other  cases 
s^Tiiptoms  of  hydropsy  and  mummification  of  the  fetus  are 
present,  conditions  which  can  begin  in  the  third  month  of 
pregnancy. 

Diagnosis. — On  account  of  its  great  prevalency  the  diag- 
nosis from  the  physical  signs  alone  is  not  difficult.  All 
cases  of  multiple  abortions  in  a  cow  herd  or  horse  stud 
should  be  looked  upon  with  suspicion,  and  until  disproven 
considered  cases  of  infectious  abortion.  As  contributory 
to  diagnosis  a  bacteriological  examination  of  the  vaginal 
discharge,  the  uterine  exudate,  the  placenta  or  the  fetus 
may  be  made.  However,  this  is  rarely  feasible  in  practice. 
Of  late  the  complement-fixation  test  has  been  extensively 
employed.  While  this  test  is  not  so  accm'ate  as  the  comple- 
ment-fixation test  for  glanders  it  nevertheless  forms  a 
valuable  contribution  to  the  diagnosis.  In  cases  of  doubtful 
reaction  (incomplete  hemolysis)  a  retest  should  be  made  in 
four  to  six  weeks.  A  negative  reaction  does  not  necessarily 
exclude  the  abortion  bacillus,  as  the  infection  may  have 
occurred  so  recently  that  the  immune  bodies  have  not  yet 
formed  in  sufficient  amount  to  bring  about  the  reaction. 
The  agglutination  test  is  also  used.  It  is  found  that  the 
blood  serum  of  cattle  suft'ering  from  infectious  abortion 
possesses  an  average  agglutinating  value  of  1000  and  may 
cause  agglutination  in  dilutions  as  high  as  16,000.  In 
healthy  cows  the  agglutinating  value  of  the  serum  is  rarely 
above  50.    So-called  "abortin,"  which  is  prepared  from  the 

abortus  bacillus  much  as  tuberculin  is  prepared  from  the 

28 


4:U  CHROXJC  INFECTIOUS  DISEASES 

tiil)orcle  liacillus,  has  failed  to  give  uniforiiily  satisfactory 
results.  The  reaction  is  a  thermic  one  with  which  are  some- 
times associated  constitutional   s^'mptoms. 

Course. — Infectious  abortion  usually  persists  in  a  herd 
for  years.  After  the  first  abortions,  often  overlooked  or 
attributed  to  other  causes  by  the  owner,  new  cases  occur 
with  a  few  weeks'  interval  between.  Finally  the  abortions 
become  more  and  more  frequent  until  a  full-term  calf  is  a 
rarity  in  the  herd.  In  time,  howe^'er,  the  al)orti(nis  occur 
at  less  frequent  intervals.  Cows  which  have  aborted  one  or 
more  times  carry  to  full  term  (become  tolerant — so-called 
"immunes").  Clean  cows  introduced  into  the  herd  may  be 
the  only  ones  to  abort.  Iltimately,  in  two  or  three  years, 
the  abortions  cease  entirely,  provided  the  herd  has  been 
kept  intact.  However,  there  are  exceptions  to  this  rule 
and  not  infrequently  individual  cows  fail  to  produce  full- 
term  calves. 

Treatment. — Once  the  disease  has  gained  a  foothold  in  a 
cow  lierd  treatment  is  rarely  successful.  The  reason  for  this 
is  that  the  germs  of  the  disease  are  within  the  uterus  and 
obviously  in  the  pregnant  animal  cannot  be  reached  with 
disinfectants.  Very  fashionable  is  the  administration  of 
l)henol.  It  may  be  administered  subcutaneously  in  doses 
of  10  c.c.  of  a  2  per  cent,  solution  during  the  fifth  to  seventh 
months  of  pregnancy  or  it  may  be  given  with  the  food.  A 
simple  method  of  dosage  is  to  make  uj)  a  .3  per  cent,  solution 
of  j)henol,  giving  to  each  cow  daily  four  ounces  of  the  solution 
in  the  food.  In  ten  days  the  dose  can  be  increased  to  sixteen 
or  even  twenty-four  ounces  daily,  provided  this  quantity  is 
given  in  two  or  three  feeds. ^  The  fundamental  ])rinciples 
underlying  the  control  of  infectious  abortion  are  the  same 
as  for  the  eradication  of  any  infectious  disease,  viz.:  (a) 
The  separation  of  the  sick  from  the  healthy,  (h)  The  dis- 
infection of  the  premises,  including  the  safe  disposal  of  the 
dead,    (c)  The  care  of  the  sick. 


•  If  }ir:iiluall.\-  lirouKhl  up  to  i(  cattU'  will  stand  enoniious  doses  of  phenol. 
A  tliousaiid-pound  hull  was  yiven  without  injury  in  one  day  nearly  2  pounds 
of  phenol  divided  into  four  doses. 


INFECTIOUS  ABORTION  435 

(a)  Cows  which  are  about  to  abort  or  ha^'e  aborted  should 
he  rem()\ed  from  the  rest  of  the  herd.  If  it  is  impossible  to 
place  them  in  a  separate  barn  they  should  be  placed  in  a 
separate  part  of  the  barn  or  at  least  one  or  two  empty  stalls 
left  between  them  and  their  neighbors. 

(6)  The  premises  should  be  thoroughly  cleaned  and  dis- 
infected and  the  dead  fetuses  and  afterbirths  rendered 
innoxious  by  burning,  boiling,  or  deep  burial.  As  the  herd 
bull  is  a  transmitter  it  is  advisable  to  disinfect  his  genital 
organs  after  each  service  by  flushing  out  the  sheath  with 
some  antiseptic  (lysol  1  per  cent.).  The  long  hairs  at  the 
end  of  the  sheath  should  be  cut  away  and  the  hair  around 
and  in  front  of  the  sheath's  opening  removed  with  clippers. 

(c)  Cows  which  have  aborted  and  are  still  discharging 
should  be  treated  by  irrigating  with  an  antiseptic  solution 
(lysol  1  per  cent.;  creolin  2  per  cent.).  At  first  this  may 
be  done  every  other  day,  later  every  third  day  and  afterward 
once  or  twice  a  week  until  all  discharge  ceases.  The  cow 
should  not  be  bred  for  about  ten  weeks  after  she  has  aborted 
and  not  then  if  still  discharging.  It  is  usually  advisable  to 
flush  out  her  genital  passages  just  before  service  with  a 
bicarbonate  of  soda  solution  (2  per  cent.). 

Prevention. — To  prevent  the  introduction  of  the  disease 
from  the  outside  all  newly  purchased,  pregnant  animals 
should  be  isolated  until  after  calving.  No  cows  should  be 
added  to  the  herd  with  any  abnormal  vaginal  discharge. 
No  bull  should  be  patronized  unless  he  is  known  to  be  clean. 
Aborting  herds  should  not  be  allowed  to  exhibit  at  fairs  or 
cattle  shows  which  is  a  common  way  of  distributing  the 
virus  of  the  disease. 

Cows  which  have  aborted  should  not  be  sold  but  kept 
in  the  herd  until  they  become  "ceased  aborters,"  unless 
they  fail  to  conceive  when  bred.  Keeping  together  the 
original  herd  will  lead  to  a  more  rapid  eradication  of  the 
disease  than  if  the  infected  animals  are  sold  and  replaced 
with  new  susceptible  ones. 

Imniuiiizatinn. — Recent  investigations  by  Bang  point  to 
the  probability  of  immunizing  cattle  against  infectious 
abortion.     He  employed  repeated  intravenous  injections  of 


436  CHRONIC  INFECTIOUS  DISEASES 

living  cultures  in  10  c,c.  doses  two  months  before  conception 
with  the  result  that  the  fetus  was  carried  to  full  term.  The 
effect  of  the  vaccination  on  the  animal,  however,  was  not 
favorable.  Later  attenuated  cultures  were  used  with  partial 
success.  In  England  cxi)criments  with  !.")()  c.c.  of  a  virulent 
culture  injected  two  months  before  breeding  gave  encourag- 
ing  results. 

INFECTIOUS  GRANULAR  VAGINITIS  OF  CATTLE. 

Colpitis  (jkaxulosa  Infectiosa  Bovum. 

Definition. — Infectious  granular  vaginitis  is  a  disease  of 
cattle  characterized  by  catarrhal  iiiHannnation  of,  and  the 
presence  of  peculiar  nodules  in,  the  vaginal  mucosa. 

Occurrence. — The  disease  is  widely  distributed  in  the 
t'nited  States.  Tn  some  communities  nearly  every  dairy 
herd  is  infected.  It  is  also  very  prevalent  in  England  and 
on  the  continent  of  Europe.  As  the  disorder  tends  to  ])revent 
conception  and  in  some  cases  induces  abortion  (?)  it  attains 
great  economic  importance. 

Etiology. — The  cause  seems  to  be  a  specific  streptococcus 
which  is  (iram-negative. 

Natural  Infection. — The  disease  is  spread  by  the  bull 
during  the  act  of  coitus.  It  may  also  be  disseminated  by 
contact  of  healthy  with  infected  cows.  Stable  litter, 
utensils,  syringes,  etc.,  or  even  the  hands  of  attendants 
contaminated  with  infectious  vaginal  discharge,  are  imi)or- 
tant  factors  of  spread.  The  disease,  therefore,  is  not  confined 
to  cows,  but  attacks  heifers,  calves  and  even  males.  In  the 
bull  the  mucous  membrane  lining  the  sheath,  external  surface 
of  the  penis,  or  even  the  urethra  becomes  infected  which 
accounts  for  the  rapid  dissemination  of  the  disease  in  a  cow 
herd  or  community  (conununity  bull).  Horses,  sheep,  and 
swine  are  innnune  to  infection. 

Symptoms. — The  juM-iod  of  incubation  from  natural  infec- 
tion is  usuall\  three  to  five  days.  A  mininunn  i)eri()<l  of  one 
day  is  recorded.  The  first  symptoms  are  those  of  an  acute, 
jiurulent  coli)itis  with  congestion,  swelling,  and  sensitiveness 


IXFECTIOrS  GRANULAR   VAGIXITIS  OF  CATTLE     437 

of  the  mucosa  of  the  vagina,  accompanied  by  some  muco- 
purulent discharge.  Later  there  appear  on  the  lateral  sur- 
faces of  the  vagina  and  in  the  neighborhood  of  the  clitoris 
a  number  of  small,  firm  nodules  or  granules  about  the 
size  of  a  hemp  seed.  At  first  they  are  dark  red,  but  later 
become  paler  (enlarged  hiiiph  follicles).  Concomitant  with 
the  granular  eruption  occurs  an  odorless,  mucopurulent,  or 
purulent  ^•aginal  discharge,  which  soils  the  vulva  and  the 
tail,  where  it  dries  to  brownish  crusts.  The  general  condition 
of  the  animal  is  not  much  disturbed.  In  about  one  month 
the  symptoms  of  acute  inflammation  subside,  the  discharge 
becomes  more  mucous,  and  the  granules  fade  to  light  red 
or  reddish-yellow.  The  process  tends  to  extend  forward 
in  the  vagina  and  may  enter  the  uterus,  causing  endometritis. 
Sterility  and  abortion  (infectious  abortion)  are  apt  to  result. 

Diagnosis. — The  recognition  depends  upon  the  contagious 
character  of  the  disease  and  the  characteristic  appearance  of 
the  granules  which  do  not  break  do\m  to  form  pustules  or 
ulcers.  In  the  vaginal  mucous  membrane  of  perfectly  healthy 
cows  a  few  enlarged  lymph  follicles  may  be  found.  Therefore 
conclusions  should  not  be  arrived  at  hastily.  In  infectious 
abortion  the  l\Tnph  follicles  may  also  become  swollen  but,  as 
a  rule,  the  nodules  are  larger,  more  discrete  and  less  numerous. 
From  vesicular  exanthema  of  cattle  infectious  granular 
vaginitis  is  distinguished  by  the  fact  that  no  vesicles,  pustules 
or  ulcers  occur,  the  general  condition  is  not  usually  dis- 
turbed and  the  bull  is  also  pronouncedly  affected  (vesicles 
and  ulcers  in  the  sheath  and  on  the  penis;  mucopiu-ulent 
discharge  from  the  uretlira).  Furthermore,  coital  exanthema 
occurs  also  in  the  horse,  sheep,  and  swine. 

Course. — ^The  course  is  prolonged,  the  disease  usually  last- 
ing for  weeks  or  months.  As  an  attack  does  not  produce 
immunity,  reinfection  commonly  occurs.  As  a  general 
proposition,  infectious  granular  vaginitis  is  a  stubborn  dis- 
ease, which  unless  treated  promptly  in  the  early  stages 
becomes  a  most  obstinate  malady. 

Treatment.— Treatment  consists  in  a  thorough  cleansing 
of  the  affected  genital  passages  with  disinfectants  which 
are  not  too  irritant.    The  disinfection  of  the  premises  should 


438  CHRONIC  INFECTIOUS  DISEASES 

also  be  made.  Where  feasible  m  separation  of  the  infected 
from  the  non-infected  slionld  l)e  practised.  The  vaijina  may 
he  flnshed  out  with  a  lukewarm  solution  of  bicarbonate  of 
soda  (2  per  cent.)  or  lysol  solution  (1  per  cent.)  \  a^inal 
tampons  made  of  gauze  impregnated  with  some  antiseptic 
in  fluid,  ointment,  or  ])()wder  form  are  considered  more 
serviceable  than  mere  irrigations,  as  the  antiseptic  is  kept 
in  longer  contact  with  the  inflamed  part.  Success  does  not 
depend,  however,  so  much  upon  the  disinfectant  used  as  the 
thoroughness  of  its  application.  Bulls  may  be  treated  as 
reconunended  in  infectious  abortion. 

Prevention.  —  Prevention    is   accomplished    by   ])racticaliy 
the  same  means  suggested  for  infectious  abortion. 


CHAPTER  VI. 
INFECTIOUS    DISEASES    DUE    TO    PROTOZOA. 

PIROPLASMOSES. 

Definition.  —  Piroplasms  are  one-celled  protozoa  which 
assume  various  shapes,  some  of  them  pear-,  some  round-, 
and  some  ring-shaped.  When  introduced  into  the  body  of  a 
susceptible  animal  they  enter  the  red  blood  corpuscles  which 
cells  they  destroy,  leading  to  anemia,  hemoglobinemia,  and 
icterus.  Piroplasms  are  transmitted  from  the  infected  to  the 
susceptible  animal  by  insects  known  as  ticks.  In  the  tick 
they  probably  pass  through  an  evolutionary  stage.  The  most 
important  pathogenic  piroplasms  and  the  piroplasmoses  they 
produce  are  the  following: 

(a)  Piroplasma  bigeminum,  causing  Texas  fever. 

(6)  Piroplasma  parvum,  causing  East  African  fever  of 
cattle. 

(c)  Piroplasma  equi,  producing  biliary  fever  of  horses. 

{(I)  Piroplasma  ovis,  causing  so-called  malarial  fever  of 
sheep. 

(e)  Anaplasma  marginale,  producing  gall  sickness  of 
cattle. 

Relationship  of  the  Tick  to  Piroplasmosis. — Animals  become 
infected  when  on  pasture  from  being  bitten  by  ticks.  These 
insects,  of  which  there  are  a  great  many  varieties,  belong  to 
the  group  Ixodina?  and  the  family  Ixodida^.  From  a  patho- 
logical standpoint  the  most  important  belong  to  the  genus 
boophilus  and  the  genus  Ixodes.  The  ticks  become  fully 
developed  either  on  the  animal  which  serves  as  host  (Texas 
fever)  or  they  leave  the  host  as  n.Mnphs  (East  Coast  fever), 
or  both  as  larvae  and  nymphs  (European  piroplasmosis). 
The  most  important  varieties  are  the  following: 

(a)  Ixodes  ricinus  (European  piroplasmosis). 


440       INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

(b)  Boophilus  (or  niarsaropiis)  annulatiis  (American, 
Australian,  East  Asian  and  Soutli  Europe  ])iroplasmoses). 

(c)  I\lni)ic(>plialus   apixMidiculatus    (East   (oast   fever). 

(d)  Dennacentor  reticulatus  (biliary  fever). 

(e)  lihipicei)halus  bursa  (malarial  fever  of  sheep). 
Texas   Fever    (Piroplasmo.vs  of  Cattle.     Souflieni    Cnttlc 

Fcwr). — Definition. — Texas  fe\-er  is  a  specific  lilood  disease 
of  cattle,  due  to  the  protozoon  Piroplasma  bigeminum,  and 
characterized  by  fever  and  hemoglobinuria.  The  causal 
germ  is  transmitted  by  ticks. 

Occurrence. — The  disease  is  indigenous  to  districts  in- 
fest(>d  with  certain  varieties  of  the  cattle  tick.  In  the  United 
States  Texas  fever  exists  permanentl\-  in  the  Southern  States. 
In  the  North,  due  to  the  cold  winters  which  kill  the  ticks, 
only  sporadic  outbreaks  take  place  in  the  summer  season, 
the  infection  being  carried  from  the  South  by  ticky  cattle. 
Native  Southern  cattle  are  tolerant  to  the  disease,  but 
Northern  cattle  brought  South  are  very  susceptible.  The 
disease  also  occurs  in  Australia,  South  America,  India  and 
throughout  Europe  (flifferent  types).  Before  the  recognition 
as  a  carrier  of  the  infection,  and  the  consequent  establish- 
ment of  a  Texas  fever  quarantine  line  across  the  Ignited 
States,  the  disease  practically  prevented  the  interchanging 
of  Northern  and  Southern  cattle. 

Etiology. — The  cause  of  Texas  fe\er  is  the  protozoon 
Piroplasma  l)igeminum.  The  transmitter  of  the  infection 
is  the  cattle  tick  of  which  there  are  several  varieties.  In 
the  I7nited  States  the  Boo])hilus  annulatus  is  the  carrier; 
in  Europe  the  Ixodes  ricinus,  in  South  America  and  Australia 
the  Bo(")])hilus  argentinus  and  australis,  and  in  South  Africa 
the  Boophilus  decoloratus  and  appendiculatus. 

The  Piro})lasma  bigeminum  is  found  in  the  red  blood 
corpuscles  during  the  fever  stage  of  the  disease.  They  are 
pear-shaped  or  round  and  usually  occur  in  ])airs.  Depending 
upon  the  number  of  i)rotozoa  introduced,  the  type  of  the 
disease  may  be  severe  (acute)  or  mild  (chronic).  During 
the  height  of  the  Texas  fever  season  (late  in  August,  earl\-  in 
Sei)tember)  the  acute  form  prevails  and  earlier  than  August 
and  later  than  S(>pteml)cr  the  milder,  chronic  tvj)e  is  met 
with. 


PIROPLASMOSES  441 

The  blood  of  an  ox  containing  the  piroplasm  is  virulent 
when  injected  into  susceptible  cattle  (subcutaneous,  intra- 
vascular, intraperitoneally) ,  but  feeding  such  blood  fails  to 
produce  the  disease.  The  parasite  will  remain  virulent  in  a 
recovered  animal  for  years. 

How  Texas  Fever  is  Spread. — As  noted,  the  cattle  tick  is 
the  carrier  of  the  causal  protozoon.  As  far  as  is  known  it  is 
the  only  carrier.  These  ticks  are  essentially  parasitic;  they 
cannot  attain  full  development  unless  they  have  access  to 
cattle.  Their  life  history  is  important,  as  the  control  and 
eradication  of  the  tick  is  naturally  followed  by  a  cessation 
of  the  disease.  The  life  history  is  simple :  A  pregnant  female 
falls  to  the  ground  from  the  skin  of  an  ox  and  soon  lays  2  to 
4000  eggs.  Depending  upon  the  temperature  and  moisture 
present,  in  from  two  to  six  weeks  a  fully  developed  embryo 
breaks  the  egg  shell  and  becomes  free.  ^Yhen  hatched  the 
little  seed  tick  is  a  very  active,  six  legged,  spider-like  insect 
which  crawls  up  the  grass  blades  and  lies  in  wait  for  an  ox, 
to  the  skin  of  which  it  attaches  itself.  The  larval  tick  can 
grow  only  when  on  cattle.  In  moist  soil,  leaves,  etc.,  it  can 
remain  alive,  however,  for  many  months,  even  living  through 
the  mild  Southern  winters,  and  be  capable  of  infecting  cattle 
the  following  spring.  In  the  more  rigorous  Northern  winter, 
however,  it  perishes.  Once  attached  to  the  skin,  the  tick 
moults,  attains  sexual  maturity,  copulates  and  fills  itself 
with  the  blood  of  its  host.  While  withdrawing  the  blood  of 
the  host  the  causal  protozoon  is  introducefl  and  the  infection 
brought  about. 

Susceptible  cattle  placed  in  tick-infested  pastures  thus 
become  infected.  This  is  commonly  observed  when  susceptible 
cattle  are  turned  on  the  usually  tick-infested  Southern  pasture 
or  are  placed  in  Northern  pastures  or  enclosures  in  which 
tick-laden  Southern  cattle  have  been  grazing  or  kept.  In 
permanently  tick-infested  districts  the  native  cattle  are 
wholly  or  partially  immune.  If  they  contract  the  disease 
at  all  the  attack  is  usually  mild.  One  attack  of  Texas  fever 
confers  a  relative  immunity,  but  the  blood  of  an  immune 
animal  remains  virulent  for  several  years.  The  disease  can 
therefore  be  spread  by  an  immune  or  recovered  animal, 
provided  the  purveying  tick  is  present. 


442       IXFECriOUS  DISEASES  DUE  TO  PROTOZOA 

Symptoms.  -After  ;i  ])cri()(l  of  iiu-uhatioii  of  eij^lit  to  ten 
(lays  following  infestation  with  ticks,  symptoms  of  fever 
ap])ear.  Tbe  temi)eratiire  ranges  from  104.9°  to  108°  F., 
the  patient  is  dull,  stupid  (in  rarer  instances  may  show 
excitement),  the  muzzle  dry  and  hot  and  the  appetite  is 
impaired  or  fails.  Quite  often  the  patients  assume  unnatural 
attitudes  when  standing  or  lying.  The  mucous  membranes 
are  icteric,  pulse  rapid,  breathing  dyspneic,  bowels  consti- 
pated and  the  fecss,  which  later  becomes  softer,  tinged  with 
blood  and  bile.  On  the  skin  of  the  scrotum  (udder),  inner 
surface  of  the  thighs,  escutcheon  and  sometimes  over  the 
whole  body  ticks  may  be  felt  and  seen.  Toward  tlie  end  of  the 
attack,  and  especially  marked  in  fatal  cases,  is  the  a])])ear- 
ance  of  hemoglobinuria,  the  urine  assuming  a  claret-wine 
color.  The  blood  is  anemic  (number  of  red  corpuscles  sinks 
from  eight  to  less  than  three  million),  poikilocytes  api)ear 
and  numbers  of  pear-shaped  or  round  i^rotozoa  can  be  seen 
in  the  red  blood  corpuscles. 

Necropsy. — In  acute  cases  the  condition  of  the  cada^■er  is 
usually  good,  but  where  the  course  has  been  protracted  it  is 
emaciated.  Ticks  are  found  on  the  skin,  especially  in  the 
region  of  the  scrotum  (udder),  inner  surface  of  the  thighs  and 
escutcheon.  The  subcutaneous  tissue  is  usually  anemic  and 
icteric.  The  spleen  is  enlarged,  often  weighing  six  or  se^'en 
pounds  and  its  parenchyma  has  become  a  dark,  pur])le  colored, 
disintegrated  mass.  The  liver  is  enlarged,  has  lost  its  natural 
brown  color  and  is  yellow  on  its  surface.  When  incis^'d  it 
shows  a  mahogany-brown  color;  from  fatty  degeneration 
the  color  is  still  lighter  yellow.  The  gall-bladder  is  distended 
with  flaky  bile  mixed  with  mucus  of  a  viscid,  stringy  con- 
sistency. The  urinary  l)lad(ler  is  filled  with  red  urine,  the 
shades  varying  from  pale  red  to  a  deep  red.  The  kidneys 
are  hyperemic,  the  lungs  are  intact  and  the  serous  coverings 
of  the  heart  show  ecchymoses. 

Diagnosis. — In  the  United  States  Texas  fever  might  be 
confused  with  antlirax,  black-leg  and  hemorrhagic  sei)ti- 
cemia.  The  presence  of  the  ticks  (in  non-tick-infested 
districts)  on  the  skin  and  the  microscopic  examination 
of  the  blood   should  cl:'af  away  all  doubt.     Clinically,  the 


PIROPLASMOSES  443 

symptoms  of  general  anemia  are  very  suggesti\'e  of  Texas 
fever.  In  anthrax  anemia  does  not  develop.  Black-leg 
attacks  only  yonng  cattle  which  show  characteristic,  crepitant 
swellings  and  no  splenic  enlargement.  The  conrse  of  hemor- 
rhagic septicemia  is  usnally  very  rigorous  and  rapid  (die  in  a 
few  hours),  no  ticks  are  present,  the  spleen  is  not  enlarged 
and  microscopically  the  bipoled  bacteria  are  visible  between 
the  blood  corpuscles. 

Course. — The  com'se  of  the  disease  is  varied.  Acute  cases 
(height  of  the  Texas  fever  season)  die  in  three  to  five  days. 
Subacute  cases  may  linger  for  three  weeks  and  terminate 
fatally.  Chronic  cases  often  recover  after  weeks  of  illness. 
In  calves  the  disease  is  ofte^j  benign,  ending  in  recovery.  As 
noted,  outbreaks  during  \'ery  hot  weather  are  more  malignant 
than  when  cooler.  Chronic  cases  are  subject  to  relapses. 
The  mortality  is  from  5  to  90  per  cent. 

Treatment. — The  patient  should  be  removed  at  once  to  a 
non-tick -infested,  shady  place  and  if  feasible  the  ticks 
removed  from  them  (hand-picking,  antiparasitic  agents). 
Internal  medication  avails  little.  Much  recommended  is 
quinine  (5  ij-v  per  os) .  Intravenous  injections  of  formalin 
(100  to  500  grams  of  a  1  per  cent,  solution),  followed  by  lysol 
internally  (I^ — lysol  5ij;  spiritus  frumenti  5iij;  aqua  Oj; 
M.  D.  S.;  hourly  one  tablespoonful  until  urine  becomes 
clear)  have  given  some  results.  Trypanroth  given  sub- 
cutaneously  or  intravenously  (up  to  200  c.c.  of  a  1.5  per  cent, 
solution;  make  up  fresh  in  distilled  water)  will  reduce  the 
number  of  parasites  but  usually  only  temporarily. 

Prevention. — The  prevention  of  Texas  fever  depends  upon 
the  eradication  of  the  carrier-tick.  Once  a  field  is  rid  of  these 
insects,  non-tick-bearing  cattle  may  be  turn(;d  into  it  with 
impunity.  The  task  of  ridding  the  United  States  of  cattle 
ticks  is  now  well  under  way.  In  the  Southern  States  an  area, 
formerly  tick-infected,  larger  than  two  ordinary  States  has 
already  been  freed.  Various  methods  of  eradication  are  in 
vogue.  Which  one  to  employ  will  depend  upon  local  con- 
ditions. The  following  briefly  describes  the  most  practical 
methods : 


444       INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

(a)  Hand  Picking. — When  only  a  few  cattle  are  kept  on 
the  farm  or  in  the  case  of  ox  teams,  removing  the  ticks  by 
picking,  currying  or  brushing  three  times  a  week  from  May 
till  December  effectually  protects  the  ])astures  from  rein- 
festation  with  pregnant  females  and  also  betters  the  con- 
dition of  the  cattle  themselves. 

(b)  Spraying  with  crude  petroleum  or  some  coal-tar  dip 
(5  per  cent.)  from  May  till  December  serves  the  same 
purpose  in  small  herds.  Sometimes  where  no  spraying 
mechanism  is  at  hand,  the  fluids  are  applied  with  sponges, 
brushes  or  with  a  syringe. 

(c)  Dipping. — In  large  herds  dipping  is  the  most  practical 
method  of  ridding  the  cattle  of  ticks.  In  many  tick-infested 
districts  community  dips  made  of  concrete  are  erected  to 
serve  a  number  of  farmers.  Baumont  crude  petroleum  is 
used  for  the  bath.  The  cattle  should  not  be  dipped  until 
after  the  shedding  of  the  winter  hair  coat.  If  they  are  to  be 
shipped  north  of  the  quarantine  line,  the  cattle  must  stand 
eight  days  to  drain  thoroughly. 

(f/)  "Soiling  Method." — The  ticky  cattle  are  placed  in  a 
tick-free  pen  for  three  weeks.  At  the  end  of  this  ])erio(l  thvv 
are  removed  to  a  second  tick-free  pen  and  kept  in  it  a  further 
three  weeks.  If  at  the  end  of  this  time  they  are  found  free 
from  ticks  they  may  be  placed  on  a  non-infested  pasture.  If 
not,  they  are  returned  to  a  pen  for  two  weeks  longer.  The 
success  of  this  i)lan  de])ends  upon  the  fact  that  all  of  the  ticks 
drop  off  the  cattle  while  in  the  pens  and  as  the  animals  are 
removed  to  a  new  pen  before  a  new  crop  of  seed  ticks  can 
hatch,  no  opportimity  for  reinfection  is  offered.  Obviously 
the  ])ens  nnist  be  thoroughly  disinfected  before  using  again. 

Freeing  l\i6-turr.s  from  Ticks. — There  are  several  methods 
of  eradicating  ticks  from  infested  pastures. 

1.  If  the  pasture  be  cultivated  for  one  year  and  all  ticky 
cattle  kept  out  of  it,  it  will  become  rid  of  ticks. 

2.  Burning  ticky  ])astures  each  si)ring  and  fall  will  keep 
them  free  so  long  as  no  ticky  cattle  are  permitted  on  them 
in  the  interim. 

3.  Early  in  September  the  cattle  are  moved  from  the 
infested   pasture    and    cleaned    of    ticks.      They   are   then 


PIROPLASMOSES  445 

placed  on  a  non-infested  pasture  and  all  contact  with  ticky 
animals  prevented.  The  original  pasture  is  kep+  free  from 
animals  until  the  following  April  when  it  will  be  free  from 
ticks.  In  the  eight  months  during  which  the  field  has  not 
been  used  for  pasture  the  seed  ticks  which  hatch  in  the  fall 
have  died  of  starvation,  having  bad  no  access  to  cattle. 

4.  Feed-lot  Method. — A  field  of  corn  or  other  forage  crop 
is  fenced  oflF  into  three  different  enclosures.  Around  each 
enclosure  a  furrow  is  plowed  and  a  board  placed  so  as  to 
prevent  the  escape  of  ticks.  The  cattle  are  placed  in  this 
field  for  a  period  of  sixty  days,  spending  twenty  days  in  the 
first  enclosure,  twenty  in  the  second  and  twenty  in  the  third. 
At  the  end  of  this  period  they  are  free  from  ticks,  as  they  were 
not  allowed  to  remain  in  any  one  of  the  enclosures  long  enough 
for  reinfestation.  In  moving  the  cattle  from  one  enclosure 
to  another  they  should  be  driven  over  plowed  ground  and 
after  they  are  taken  out  the  furrow  should  be  sprayed  witli 
crude  petroleum.  Obviously  the  cattle  should  not  be  fed 
hay  nor  given  water  from  tick-infested  pastures. 

Protective  Inoculation. — Susceptible  cattle  shipped  to 
tick-infested  regions,  especially  animals  from  six  to  eighteen 
months  old,  may  be  immunized  against  Texas  fever  by  one  of 
the  following  methods: 

1.  The  animals  are  confined  in  a  tick-free  enclosure  and 
a  small  number  of  (25  to  50)  virulent  seed  ticks  placed  upon 
them.  A  month  later  a  greater  number  of  seed  ticks  (2  to 
400)  is  used.  This  will  often  produce  a  non-fatal  t^1^e  of 
Texas  fever  which  renders  the  animal  immune  to  natiu-al 
infection. 

2.  The  susceptible  young  cattle  are  injected  subcuta- 
neously  with  the  defibrinated  blood  of  a  native  calf  or  a 
recovered  adult  animal.  Usually  eight  to  ten  days  after  the 
injection  the  animal  develops  symptoms  of  anemia,  hemo- 
globinuria and  sometimes  bloody  diarrhea.  ^Microscopically, 
the  blood  will  show  a  great  diminution  of  red  blood  corpuscles 
and  will  contain  a  few  piroplasms.  In  eight  to  ten  days  these 
symptoms  temporarily  disappear  but  a  month  later  usually 
a  second  reaction  sets  in  which  lasts  only  eight  to  ten  days 
but  is  milder  in  t^i^e,  the  red  blood  corpuscles  showing  only 


44(i       INFECTIOUS  DISEASES  DUE   TO  PROTOZOA 

a  few  piroplasms  of  atypical  form.  If  cattle  so  treated  are 
two  months  later  turned  into  infested  pastures  a  large  pro- 
portion of  them  will  resist  natural  infection.  Some  of  them, 
howe\er,  will  show  symptoms  of  fever  which  is  usually 
followed  by  recovery.  The  losses  from  this  method  of 
immunization  are  about  10  per  cent.  Some  animals  of  low 
resistance  die  during  the  process  of  immunization.  This 
method  seems  more  controllable  than  the  former  one  and  is 
now  much  em])loyed  to  prevent  losses  among  imported 
susceptible  cattle. 

Quarantine  Line— The  United  States  Government  has 
established  a  quarantine  line  which  extends  from  the  seacoast 
east  of  Norfolk,  Virginia,  across  the  country  to  the  coast  of 
California  near  San  Francisco.  This  line  is  a  very  irregular 
one  and  is  varied  from  time  to  time  as  counties  just  south  of 
it  are  freed  from  ticks.  Roughly,  at  present,  the  line  extends 
through  the  centre  of  Virginia,  westward  along  the  north 
boundary  of  North  Carolina,  through  the  State  of  Tennessee, 
along  the  north  boundary  of  Arkansas  to  the  centre  of  the 
north  boundary  of  Oklahoma,  where  it  drops  suddenly 
taking  a  southwesterly  course  imtil  it  reaches  the  Mexican 
line,  along  the  north  border  of  which  it  proceeds  westward 
until  it  reaches  the  east  boundary  of  California  which  it 
follows  north  as  far  as  the  latitude  of  San  Francisco  where 
it  again  turns  westward  to  the  coast. 

Piroplasmosis  of  European  Cattle  (hifcctiou^s'  Ilrwof/Iohin- 
uria  of  f/ic  O.v.  '  'Red  H  'afer'' ' ) . — Definition. — Piroplasmosis  of 
European  cattle  is  an  infectious  blood  disease  very  similar 
to  if  not  identical  with  American  Texas  fever.  The  disorder 
is  transmitted  by  a  variety  of  the  cattle  tick. 

Occurrence. — This  piroplasmosis  is  generally  distributed 
throughout  Europe  (Germany,  Russia,  Finland,  Rumania, 
etc.),  where  it  assumes  usually  an  enzootic  form,  outbreaks 
occurring  most  commonly  among  cattle  on  pasture  in  the 
spring   and   summer   months.      From   tick-infested   fcrage, 

'  Tlio  "rod  \v:ili>i"  i>r  Ihilisli  (  ipluiiibia  and  of  llio  Northwestern  I'liitod 
States,  accordiiiK  to  Hadwiii,  is  not  ilue  to  protozoa,  but  to  poisoning  witli 
oxalic  acid  from  th[»  wot,  undrained  and  infertile  pastures.  The  disorder, 
which  is  very  fatal,  usually  occurs  only  among  adult  cattle. 


PIROPLASMOSES  447 

stahle-fed  cattle  are  occasionally  infected.  Cows  and  year- 
lings are  most  susceptible.  The  disease  also  attacks  sheep 
and  goats.  Badly  tick-infested  pastures  are  permanent 
sources  of  infection,  particularly  wet  woods  pastures  and 
boggy  fields  which  adjoin  brush  and  timber  lands.  Native 
calves  are  more  resistant  than  adults  and  native  cattle  with- 
stand the  attack  better  than  imported  animals.  One  attack 
does  not  produce  permanent  immunity,  as  the  same  animals 
may  repeatedly  suffer  from  the  disorder. 

Etiology. — The  cause  of  the  disease  is  the  protozoon 
Piroplasma  bigeminum,  which  is  transmitted  by  the  European 
cattle  tick,  the  Ixodes  ricinus  (I.  redubius),  which  is  harbored 
in  grass,  brush,  bushes,  etc.,  especially  on  low  swampy  lands. 
The  life  history  of  this  tick  is  somewhat  different  from  that  of 
the  American  cattle  tick.  The  female  does  not  lay  so  many 
eggs  and  the  hatching  period  is  longer  (six  weeks).  The 
larvae  leave  the  cattle  three  to  five  days  after  attaching 
themselves  to  the  skin  and  on  the  ground  develop  into 
nymphs  in  about  four  Aveeks.  They  then  reattach  them- 
selves to  the  skin  of  an  animal,  remain  three  to  five  days, 
drop  to  the  ground  and  in  the  following  eight  weeks  develop 
to  sexually  mature  ticks  which  again  attach  themselves  to  a 
host,  suck  its  blood  and  copulate.  Therefore  the  larvae, 
nypmhs  and  sexually  dcA'eloped  ticks  are  capable  of  carrying 
the  infection.  The  time  which  lapses  between  the  laying  of 
the  eggs  and  the  dropping  ofT  of  the  pregnant  female  is 
about   nineteen   weeks   under   average   conditions. 

Symptoms. — The  period  of  incubation  is  ten  days.  The 
first  sympioms  are  high  fever  (106°  F.),  which  is  soon  followed 
by  diarrhea.  About  the  second  day  the  characteristic  hemo- 
globinuria appears  and  the  lu'ine  becomes  red.  The  shade 
of  red  may  vary  from  a  light  claret-wine  to  a  dark  tar-like 
color.  The  patient  rapidly  becomes  anemic  and  the  mucous 
membranes  icteric.  In  some  cases  there  is  marked  weakness 
of  the  hindquarters.  The  blood  of  the  animal  is  thin,  very 
dark  colored,  and  its  serinn  is  stained  red  (hemoglobinemia). 
Microscopically  (blood  drawn  from  anear  vein),  pear-shaped, 
round  or  rod-shaped  ])rotozoa  are  seen  in  the  red  corpuscles 
with  proper  staining. 


448       INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

Prognosis. — If  the  cattle  are  iniinediately  taken  off  the 
infested  pastures  and  all  ticks  removed  from  them  recovery 
usually  follows  in  about  two  weeks,  provided  the  attack  has 
been  acute.  On  the  other  hand,  where  the  animals  are  left 
on  the  infested  fields  or  where  the  outbreak  has  been  vevy 
severe,  the  jiatients  die,  the  disease  assuming  a  chronic  form 
with  symptoms  of  anemia,  emaciation,  and  cachexia. 

Treatment. — The  removal  of  the  cattle  from  the  infested 
pastures  and  the  eradication  of  the  ticks  (oil  dips)  are 
essential.  Internally  individual  i)atients  are  treated  symp- 
tomatically. 

Prophylaxis. — Tick-infested  pastures  should  be  avoided. 
Tile  draining  and  tilling  such  fields  are  indicated.  Where 
this  is  not  possible  the  brush  should  be  cut  off  and  the  fields 
burned  over  as  recommended  in  Texas  fever.  Dipping  the 
ticky  cattle  is  indicated. 

Protective  Inoculation. — The  value  of  protective  inocula- 
tion (3  c.c.  of  fresh  calf's  blood)  is  still  in  dispute.  In  some 
outbreaks  the  inoculation  material  seemed  too  weak  and  in 
others  too  strong. 

East  African  Coast  Fever  {RJwdesian  Red  Water). — Defi- 
nition.— East  African  fever  is  a  form  of  piroplasmosis  in 
cattle  due  to  the  Piroplasma  i)ar\'um.  Contrary  to  Texas 
fever  it  cannot  be  artificially  transmitted  by  blood. 

Occurrence. — The  disease  occurs  along  the  East  African 
coast  where  it  has  existed  for  a  long  time  in  a  latent  form. 
It  has  spread  into  the  interior  and  has  caused  great  losses 
among  the  cattle  of  Transvaal  and  Riiodesia. 

Etiology. — The  disease  is  caused  by  the  Piroplasma  par\um, 
a  small  rod-like  protozoon.  ^'everal  varieties  of  ticks,  which 
in  the  earlier  stages  of  their  develojjment  have  sucked  the 
blood  of  infected  cattle  (Rhipicephalus  ap])endiculatus,  U. 
Evertsi,  sinus,  nidens,  and  capensis)  are  responsible  for  its 
spread.  The  parasite  does  not  pass  through  the  egg  as  in  the 
case  of  Texas  fever,  and  the  disease  cannot  be  transmitted 
from  immune  animals  to  healthy  cattle.  The  infection  takes 
place  only  among  young  cattle  when  on  i)asture.  Adult 
animals  are  immune.  As  noted,  the  disease  cannot  be  trans- 
mitted by  the  blood,  although  transmission  has  been  accom- 


PIROPLASMOSES  449 

plished  to  susceptible  animals  by  introducing  intra-abdomin- 

ally  large  pieces  of  spleen. 

Symptoms.— The  period  of  incubation  is  ten  to  twelve 

days.    The  first  symptoms  are  those  of  high  fever,  salivation, 

bloody  diarrhea,  swelling  of  the  lymph  glands  of  the  throat, 

emaciation,  and  weakness.     Anemia  and  hemoglobinuria  are 

usually  not  present.     The   appetite  of    the  patient  may 

be  retained  until  the  last  stages. 

Prognosis.— The  disease  is  very  malignant,  the  mortality 

among  young  cattle  reaching  60  to  90  per  cent. 

Prophylaxis.— Is  similar  to  that  of  Texas  fever  and  depends 

upon  the  eradication  of  the  tick.    The  value  of  blood  and 

serum  inoculations  is  very  questionable. 
Piroplasmosis  of  the  Horse  (Bilianj  Fewr)  .—Definition.— 

The  piroplasmosis  of  horses  is  an  infectious  blood  disease 

which  occurs  chiefly  in  Italy,  Russia,  and  also  in  Africa  and 

India.    It  is  due  to  the  Piroplasma  equi. 

Occurrence.— The  disease  occms  so  far  as  reported  only 
in  the  countries  noted  above.  In  Russia  it  is  most  common 
among  young  native  horses  which  run  on  low  swampy 
pastures.  Aged  horses  imported  from  non  infected  localities 
are,  however,  susceptible. 

Etiology.— The  disease  is  due  to  the  Piroplasma  equi,  a  small 
polymorphous  parasite  found  in  the  red  blood  corpuscles. 
The  carriers  of  the  infection  are  several  varieties  of  ticks. 
In  Russia  the  Dermaccntor  reticulatus  and  in  Africa  the 
Rhipicephalus  Evertsi  are  the  carriers.  Besides  horses, 
asses,  and  mules,  zebras  and  quaggas  take  the  disease. 
The  disease  may  be  transmitted  by  blood  from  immune 
horses.  While  one  attack  produces  immunity  this  immunity 
is  readily  overcome  by  anything  which  decreases  the  resist- 
ance of  the  animal  (hard  work,  other  diseases).  Imported 
horses  are  much  more  susceptible  than  natives. 

Symptoms.— The  period  of  incubation  is  about  fourteen 
days,  after  which  there  develops  a  remittent  fever  with  great 
heart  weakness,  rapid  pulee,  icteric  discoloration  of  the 
mucous  membranes,  hemorrhage  from  the  conjunctiva, 
great  mental  depression,  dyspnea,  constipation  followed  by 
diarrhea,  emaciation,  polyuria  and  yellow  discoloration  of 
29 


4,")()       IXFECTIOl'S  DISEASES  DUE   TO   I'h'OTOZOA 

the  urine.  Microscopieally,  the  protozoa  are  found  in  the 
red  blood  corpuscles .  The  course  of  the  disease  is  \ery 
varied.  In  acute  cases  death  may  result  in  two  to  five  days. 
In  chronic  cases  the  course  is  two  to  four  weeks  or  it  may 
extend  (n-er  many  months. 

Diagnosis. — From  horse  sickness  piroplusmosis  of  horses 
is  usually  distinguished  by  the  presence  of  icterus  and  the 
absence  of  edematous  swellings.  A  positive  diagnosis  can 
only  be  made  by  finding  the  piroplasma  in  the  red  blood 
corpuscles. 

Treatment. — No  successful  medicinal  treatment  has  been 
found.  As  a  prophylactic  measure,  keeping  the  animals 
off  infested  ])astures  during  the  hot  months  is  recommended. 
The  importation  of  solipeds  should  be  made  only  during  the 
cold  season  and  confined  to  adult  animals.  Protecti^•e 
inoculation  with  1  c.c.  of  infected  colt  blood  seems  to  be 
successful. 

Piroplasmosis  of  Sheep. — Definition. — This  is  an  infectious 
l)lood  disease  of  sheep  occurring  mostly  in  the  bottom  lands 
along  the  Danube  River  in  Rumania.  Low  swampy  pastures 
are  also  infectious.  Following  floods  the  disease  is  observed 
to  a  marked  extent. 

Etiology. — The  cause  is  the  l*ir()])lasma  oN'is  which  very 
closely  resembles  the  riro]:)lasma  bigeminum.  The  disease 
is  spread  by  the  tick  Rhipicephalus  bursa.  The  period  of 
incubation  is  eight  to  ten  days. 

Symptoms. — The  syiu])t()ms  are  those  of  fever,  languor, 
anemia,  icterus,  hemoglobinuria,  hematuria,  and  bloody 
diarrhea.  Death  usually  results  in  two  to  five  days.  Oc- 
casionally the  disease  assumes  a  milder  form  and  manifests 
itself  by  sym])toms  of  bowel  catarrh,  fever  and  anemia.  One 
attack  ])roduces  imnumity.  Transmission  by  blood  can  be 
made.  The  mortality  is  50  to  60  per  cent,  of  the  adult  sheej), 
and  all  young  lambs  (three  to  four  months)  die.  Co'nales- 
cence  consumes  several  weeks. 

Treatment.— Internally,  sul])hate  of  quinine  (gr.  viij 
twice  daily)  and  (TJanber  salts  (,*j  ij)  are  recommended. 
Prevention  consists  in  keeping  the  slice])  from  infected 
pastures. 


77?  YPANOSOMIASIS  4.')1 


TRYPANOSOMIASIS. 


Dourine.' — Definition. — Doiirine  is  a  specific  infectious 
trypanosomiasis  of  breeding  horses  and  asses,  spread  by 
coitus.  It  is  characterized  by  two  distinct  chnical  stages, 
viz.,  a  primary  stage  which  is  a  local  disease  of  the  genital 
organs,  and  a  secondary  stage  of  general  infection,  which 
induces  nervous  symptoms  (polyneuritis),  skin  lesions,  and 
emaciation. 

Occurrence. — Dourine  probably  originated  in  the  Orient, 
from  where  it  spread  with  the  Arabian  horse  to  Europe. 
It  is  widely  prevalent  in  Russia,  Rumania,  Spain,  and 
Algiers.  The  disease  has  invaded  Germany,  Austria  and 
France  and  Switzerland  from  time  to  time  but  vigorous 
veterinary  police  regulations  have  held  it  in  abeyance. 
The  United  States  has  witnessed  sporadic  outbreaks,  the 
infection  evidently  spreading  from  imported  European 
stallions.  In  1885  it  was  reported  in  Illinois,  in  1892  in 
Nebraska,  in  1901  in  South  Dakota  (Pine  Ridge  and  Rosebud 
Indian  reservations),  in  1903  in  Iowa  and  in  1911  again  in 
Iowa.  Since  this  date  no  further  outbreaks  have  been  noted. 
By  the  vigorous  methods  of  suppression  employed  by  the 
United  States  Bureau  of  Animal  Industry,  all  of  the  above 
cited  outbreaks  were  effectually  controlled  and  the  disease 
eventually  stamped  out.  As  dourine  is  a  chronic  disease, 
often  difficult  to  diagnose  and  usually  fatal,  which  spreads 
readily  among  breeding  horses,  its  economic  importance  is 
great. 

Etiology. — The  cause  of  dourine  is  the  protozoon  Try- 
panosoma equiperdum  discovered  and  described  in  1896 
by  Rouget.  In  the  United  States  the  presence  of  this  para- 
site was  first  demonstrated  in  1911  (Iowa  outbreak)  by 
Dr.  John  R.  Mohler  of  the  Bureau  of  Animal  Industry 
which  conclusively  established  the  identity  of  the  American 
with  the  dourine  of  Europe,  Asia  and  Africa. 

Natural  Infection. — Susceptible  mares  are  infected  by  dis- 
eased stallions  during  copulation,  the  urethral  discharges 

'  From  the  Arabic,  meaning  unclean. 


452       INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

containing  the  causal  trypanosomes.  Likewise  a  mare 
suffering];  from  the  disorder  may  infect  a  stalHon  wliile  he  is 
serving  her.  A  transmission  by  the  stalHon  from  a  diseased 
to  a  healthy  mare,  without  the  stallion  himself  becoming 
infected,  also  occurs.  The  trypanosomes  penetrate  the 
intact  mucous  membranes  of  the  genital  tract  and  enter  the 
blood.  Insect  transmission  is  probable  but  so  rare,  if  it 
occur  at  all,  as  to  be  negligible.  Dogs,  cats,  rabbits,  rats, 
white  mice,  and  sheep  have  been  successfully  inoculated. 
Dogs  die  in  two  or  three  months  after  becoming  greatly 
emaciated.  Rabbits  emaciate  and  die  in  two  to  eight  months, 
wdiile  white  mice  succumb  to  general  septicemia  in  three  to 
five  days  following  intraperitoneal  inoculation. 

Symptoms. — The  period  of  incubation  ^'aries  from  five  to 
thirty  days  or  longer  (probably  several  months).  Following 
the  incubative  period  the  local  symptoms  of  the  first  stage 
appear. 

Primary  Stage. — In  stallions  there  is  swelling  of  the  penis 
first  noticed  in  the  glans  but  later  involving  the  whole 
organ.  The  prepuce  becomes  edematous,  but  is  not  sensitive 
to  the  touch.  The  edema  may  involve  the  ventral  abdominal 
wall  and  scrotum.  The  testes  may  also  swell.  From  the 
urethra  is  discharged  a  thin,  yellow  serum-like  fluid  which 
drips  away  more  or  less  continuously  (in  European  outbreaks 
the  urethral  discharge  is  thicker,  more  purulent).  In  three 
or  four  days  small  vesicles  a])pear  on  the  ])enis.  In  twelve  to 
thirty-six  hours  the  vesicles  erupt,  discharging  a  thin,  j'ellow 
fluid,  leaving  behind  raw  ulcers  which  tend  to  coalesce  with 
those  adjacent.  The  ulcers  heal  rapidly  but  leave  behind 
white,  non-pigmented,  ])ermanent  scars.  The  stallion  may 
show  stranguria  and  increased  sexual  desire  (frequent 
erections).  They  may  attempt  to  cover  mares  but  usually 
full  erection  of  the  penis  fails.  The  prei)utial  and  inguinal 
lymph  glands  become  swollen.  In  some  cases  abscess  of 
the  testicle  with  sloughing  lias  been  noted.  In  mares  the 
earlier  symptoms  may  be  easily  overlooked  (range  horses). 
There  is  edema  of  the  vulva,  constant  erection  of  the  clitoris, 
and  a  mucopurulent  discharge  which  soils  the  tail  and 
buttocks.    The  discharge  is  similar  to  that  from  the  penis 


TRYPANOSOMIASIS  453 

of  the  male.  In  a  short  time  papules,  vesicles,  and  ulcers 
appear  on  the  external  skin  of  the  vulva  and  on  the  vaginal 
mucous  membrane.  The  ulcers,  although  angry  looking  at 
first,  heal  readily,  but  leave  behind  permanent,  puckered, 
pitted  scars  lighter  (white  in  skin)  in  color  than  the  sur- 
rounding skin  or  mucosa.  The  mares  show  estrum-like 
s\-mptoms  (switch  tail,  urinate  frequently).  Sometimes 
edema  of  the  udder  and  ventral  wall  of  abdomen  is  present. 

In  some  cases  the  above-described  local  symptoms  may  be 
mild  and  remain  unobserved.  In  such  cases  the  general 
symptoms  of  the  second  stage  of  the  disease  are  noted  first 
and  the  traces  of  the  local  stage  then  looked  for. 

Secondary  Stagc.^The  second  stage  aflects  stallions  and 
mares  alike.  Sometimes  several  months  may  elapse  between 
stages.  Anything  which  tends  to  lower  the  resistance  of 
the  patient  (exposure,  fatigue,  breeding)  may,  however, 
precipitate  the  second  stage.  In  European  outbreaks  the 
first  s^Tnptom  of  the  second  stage  is  the  appearance  of  luti- 
caria-iike  swellings  (so-called  plaques)  of  about  the  size  of 
a  silver  dollar,  usually  round  or  half-round  in  form  with 
the  centres  depressed.  The  hairs  over  the  swellings  are 
commonly  erect.  When  pmictiued  a  blood-stained  seriun 
exudes  from  the  wound.  The  favorite  seats  of  the  plaques 
are  the  croup  (near  tail  root),  chest  wall,  neck,  under  the 
belly  and  chest.  The  plaques  usually  disappear  in  one  to 
eight  days  to  be  followed  by  a  new  crop.  The  alternate 
appearance  and  disappearance  of  the  plaques  may  continue 
for  several  months  and  form  a  very  characteristic  symptom  of 
dourine.  In  some  of  the  American  outbreaks,  however,  no 
plaques  were  observed  (overlooked?).  There  is  generally 
pruritis,  causing  the  patient  to  rub  and  scratch  the  skin. 

Xenous  Sympioms.— The  nervous  disturbance  of  the 
second  stage  consist  largely  in  motor  paralysis  principally 
of  the  peripheral  motor  nerve  (polyneuritis,  perineuritis). 
The  following  nerves  are  most  commonly  affected :  Facial 
nerve,  producing  symptoms  of  unilateral  facial  paralysis; 
the  (recurrent)  inferior  larjmgeal  nerve,  leading  to  roaring; 
the  femoral  nerve,  causing  symptoms  or  crural  paralysis; 
the  great  sciatic  nerve,  to  a  swinging-leg  lameness,  the  limb 


454       INFECTIOUS  DISEASES  DUE   TO   PROTOZOA 

bc'in^  dragged;  iKToncal  nerve,  causing  kiuickling  in  tlie  hind 
fetlock  and  stumbling  behind;  the  obturator  ner\e,  to  s])read- 
ing  of  the  gait  behind  with  abduction  of  the  limbs;  oculo- 
motor nerve,  to  paralysis  of  the  ui)per  eyelid;  i)udic  nerve,  to 
paral\sis  of  the  penis.  Naturally  not  all  of  these  paralyses  are 
noted  in  any  one  case,  but  in  practically  every  case  some  of 
them,  especially  those  involving  the  hindliml)s,  will  be 
observed.  Associated  with  the  ])eripheral  ])aralysis  symj)- 
toms  of  hyperesthesia  are  often  present.  Many  patients  are 
extremely  sensitive  when  the  skin  is  touched  or  pricked  with  a 
pin.  In  some  cases  if  the  back  be  stroked  the  horse  suddenly 
arches  it  downwardly  and  seeks  to  evade  the  examiner. 
Quite  frequently,  during  rest,  the  animal  may  show  crani])- 
like  contractions  of  the  muscles  of  a  leg,  holding  the  member 
in  the  air  (as  in  "straw  cramp").  Xot  infrequently  atrophy 
of  paralyzed  muscular  groui)s  follows.  While  in  stallions 
the  genesic  instinct  is  well  preserved,  on  account  of  the 
partial  paralysis  of  the  penis  which  pre\'ents  complete 
erection  of  the  organ,  they  are  unable  to  serve  mares. 

Spinal  paralysis  is  not  a  common  complication,  although 
some  jjatients  become  completely  paralyzed  behind. 

An  important  sym])tom  of  the  secondary  stage  is  marked 
emaciation.  In  some  instances  the  patients  emaciate  to 
skeletons,  losing  fully  oO  per  cent,  of  their  normal  weight  and 
presenting  a  peculiar  tucked-u])  appearance  of  the  flanks. 
As  further  symi)t()ms  may  be  noted  swelling  of  the  lymph 
glands  in  the  throat  and  inguinal  regions  and  decubital 
gangrene  of  the  skin.  Occasionally,  nasal  catarrh,  con- 
junctivitis, fibrinous  ])neum(mia.  arthritis  and  tendovagin- 
itis, iritis  and  albuminuria  are  observed.  The  temperature 
often  remains  normal  throughout  the  attack,  altiiough  an 
atyi)ical  fever  is  not  infrequent.  Tlie  appetite  of  the  patient 
is  usually  well  preserved. 

Diagnosis. — In  isolated  cases  with  uncertain  history  the 
diagnosis  from  the  clinical  symptoms  alone  is  often  difhcult. 
In  the  Tnited  States  where  no  other  trypanosome  disease 
among  horses  is  known,  the  microscopic  determination  of  the 
Trypanosoma  equiperdum  is  clinching.  However,  in  our 
climate  this  protozocin,  which  exists  in  the  urethral  or  vaginal 


TR  YPA  NOSOMI A  SIS  455 

discharge,  plaques,  and  edematous  swellings,  is  very  scarce 
and  difficult  to  find.  Negative  evidence,  therefore,  in  this 
regard  would  not  be  convincing.  Of  diagnostic  value  are 
the  plaques,  nerve  symptoms  (paralysis),  and  the  marked 
emaciation  of  the  patient.  All  breeding  horses  and  asses 
showing  these  should  be  considered  suspects.  Animal  in- 
oculations (dog,  mouse,  rabbit)  may  also  be  employed. 
When  in  the  primary  stage  dourine  might  be  confused  with 
coital  exanthema  which  sometimes  looks  strikingly  like  it. 
However,  this  is  a  benign  disease,  healing  readily  and 
leaving  behind  no  permanent  scars  and  is  followed  by  neither 
plaques  nor  nerve  symptoms.  Traumatic  lesions  of  the 
vagina  from  excessive  copulation  (range  mares)  is  character- 
ized by  wounds  and  ecchymoses  (purple  patches)  rather  than 
by  vesicles  and  ulcers.  The  mallein,  guinea-pig  or  comple- 
ment-fixation tests  suffice  to  differentiate  between  glanders 
of  the  sexual  organs  and  dourine.  Paralysis  due  to  infectious 
anemia,  forage  poisoning,  etc.,  affects  geldings  as  well  as 
stallions  and  mares. 

Course.— In  northern  latitudes  the  course  is  chronic;  in 
southern  usually  acute.  In  some  cases  the  second  stage, 
beginning  wath  the  development  of  the  cutaneous  plaques 
follows  closely  the  first  stage.  The  nerve  symptoms 
(paralyses)  may  not  develop,  however,  until  weeks  or  months 
later.  The  duration  of  the  whole  attack  may  extend  over 
one  or  more  years.  Obviously  any  factor  which  reduces 
the  resistance  of  the  patient  (poor  care,  insufficient  food; 
breeding,  etc.),  will  shorten  the  duration.  Exacerbations 
and  remissions  during  the  course  are  common. 

Prognosis.— The  prognosis  is  bad.  Fully  50  to  80  per  cent, 
of  the  animals  attacked  die.  A  few  recover  when  in  the 
first  stage  of  the  disease,  the  second  stage  failing  to  de- 
velop. It  is  doubtful  whether  cases  in  the  second  stage  ever 
recover. 

Treatment.— Internal  medicinal  treatment  (arsenic,  atoxyl, 
bichlorid  of  mercury,  intravenous  injections  of  tartar  emetic, 
arsenophenylglycin,  cacodylate  of  soda,  etc.),  has  been 
tried  with  indifferent  success  in  countries  permanently 
infected  with  dourine.     In  the  United  States  no  attempt  to 


4o()       INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

treat  the  patients  should  be  made.  All  affected  animals 
should  be  killed.  In  some  instances  the  castration  of  stallions 
suffering;  from  the  first  stages  of  the  disease  has  been  followed 
by  recovery.  A])])arently  toured  animals  can  harbor  virulent 
trypanosomes  for  months.  All  sus])c('ted  and  true  outbreaks 
should  be  prom])tly  re])ortcd  to  the  State  authorities. 

Surra. — Definition. — Surra  is  a  specific  bloofl  disease  of 
Asiatic  horses,  mules,  camels,  and  dogs,  due  to  the  Trypano- 
soma evansi,  transmitted  by  biting  insects.  It  is  character- 
ized by  high  fever  (early  stages),  edemas  of  the  skin,  urti- 
caria, peteclujE  of  the  mucous  membranes.  Later  the 
patients  become  anemic,  weak,  and  emaciated. 

Occurrence. — Surra  exists  in  Asiatic  countries,  and  is  a 
common  disease  in  the  I'hilipi)ine  Islands,  where  it  affects 
horses  and  occasionally  carabao  and  cattle  causing  consider- 
able losses.  The  disease  is  most  j^revalent  in  swampy  dis- 
tricts in  the  hot  months  where  horse  fiies  abound. 

Etiology. — The  Tryi)an()S()ma  evansi,  which  is  introduced 
into  the  blood  of  susceptible  animals  by  species  of  horse  flies 
(Tabanus  tropicus,  T.  lineola,  Stomoxys  calcitrans).  Cattle 
and  zebras,  which  are  only  slightly  susceptible  to  the  disease, 
are  virus  carriers. 

Symptoms. — The  ])erio(l  of  incubation  is  four  to  thirteen 
days.  The  disease  begins  with  fe\er  (105.8°  F.),  which  lasts 
four  or  five  days,  the  hair  coat  becomes  rough,  the  joints 
swell,  and  later  edemas  appear  under  the  belly  and  in  males 
in  the  prepuce.  Pctcchiic  api)ear  in  the  nuicous  mem- 
branes (eye),  followed  l)y  })aleness,  and  in  the  latter  stage  the 
conjunctiva  presents  a  marked  grayish-white  appearance. 
The  fever  usually  becomes  intermittent,  the  patient  very, 
anemic  and  notwithstanding  good  a])petite  loses  flesh  rapidly. 
In  the  blood  tlu;  Trypanosoma  evansi  is  found,  especially 
in  the  beginning  of  a  febrile  attack. 

Course. — The  course  is  usuall}'  one  or  two  months,  rarely 
does  death  ensue  in  one  or  two  weeks. 

Prognosis. — Bad.    Nearly  all  cases  die. 

Treatment. — In  permanently  infected  districts,  arsenic 
(gr.  x-xv  daily  for  ten  days  in  powder  form  as  a  bolus  or 
electuary)   has  given  good  results.      Atoxyl   (5j-v  of  a  4 


TRYPANOSOMIASIS  457 

per  cent,  solution  siibcutaneously)  given  at  the  same  time 
with  arsenic  (gr.  x-xv  per  os)  was  less  successful. 

Prevention.— Ridding  the  infested  districts  of  fly  carriers 
(cutting  lirush.  draining  fields,  tillage,  cleanliness  about 
stables)  pasturing  only  at  night  when  the  flies  do  not  swarm, 
applying  agents  to  the  skin  to  keep  flies  away  (creolin, 
petroleum),  and  encouraging  the  growth  of  citronella  grass 
are  helpful. 

In  non-infected  localities  quarantine  should  be  established 
against  animals  from  infected  countries.  The  killing  and 
cremation  of  afl  infected  animals  are  indicated.  By  taking 
the  temperatvues  frequently  during  fresh  outbreaks,  making 
blood  examinations  and  animal  inoculations  (rats,  mice) 
the  animals  harboring  the  tr^-panosomes  may  be  identified 
and  destroyed  leading  to  the  eradication  of  the  disease  in 
districts  and  countries  where  it  has  not  yet  gained  a  firm 
foothold. 

Nagana  (Tsetse  P/^m.?^).— Definition.— Xagana  is  an 
African  trj-panosomiasis  of  horses  and  cattle,  jnore  rarely 
in  sheep,  goats,  and  dogs,  due  to  the  Trji^anosoma  brucei 
and  transmitted  by  the  tsetse  fly.  In  character  it  much 
resembles  surra. 

Occurrence. — Xagana  was  formerly  wide-spread  in  Central 
and  South  Africa,  but  of  late  years  has  grown  less  common 
(disappearance  of  virus-carrying  game?).  Low,  swampy, 
river  countries  are  most  infectious. 

Etiology.— The  Tr\-panosoma  brucei.  which  is  transmitted 
from  animal  to  animal  by  the  bite  of  the  tsetse  fly  (Glossina 
morsitans)  or  other  closely  related  flies  (Gl.  fusca,  Gl. 
pallidipes,  etc.). 

Symptoms. — In  horses  the  period  of  incubation  is  two  to 
ten  days.  The  symptoms  are  high  fever  (104°  to  105.8°  F.); 
congestion  of  mucous  membranes  (eye) ;  edematous  swelling 
of  conjunctiva  (with  profuse  lacrimosis);  throat,  legs, 
under  belly,  prepuce  (in  males);  the  tr^-panosomes  being 
found  in  the  blood  during  the  fever  stages.  Later  the  fever 
assumes  an  intermittent  or  remittent  t}-pe,  the  patient 
becomes  anemic  (pale,  icteric  mucous  membranes),  emaciated 
and  very  weak,  especially  in  hind  parts,  finally  gets  down 


4r),S       IXFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

aiul  (lies  of  iiuinition.  The  ap]K'tite  is  well  retained  throujjh- 
out  the  disease.  In  some  cases  keratitis,  corneal  abscess, 
iritis  and  blindness  develoj)  dnrinji  the  attack.  Trticaria 
(l)la(|nes)    may   also   be   noted   occasionally. 

Diagnosis. — Depends  upon  a  knowledge  of  the  prevalency 
of  the  disease  in  the  district,  the  symptoms  of  remittent 
fever,  edemas,  emaciation  and  weakness  (in  spite  of  ^ood 
appetite),  and  the  demonstration  of  the  tryj)anosomes  in 
the  lymph  glands,  blood  and  edematous  swellings.  When  the 
microscopic  findings  are  negative,  dogs  should  be  inoculated. 

Prevention. — Same  as  in  Surra. 

Mai  de  Caderas.'— Definition. — ^lal  de  Caderas  is  a 
South  American  disease  of  horses  due  to  the  Trypanosoma 
equinum.  It  is  characterized  by  fever,  paralysis  of  the 
liind  parts,  urticaria,  edemas  of  pendent  portions  of  the  body, 
keratitis,  anemia  and  emaciation. 

Occurrence.  —The  disease  is  foinid  in  Brazil,  Hatavia, 
Argentine,  Paraguay,  and  on  the  islands  of  the  delta  of  the 
Amazon.  Like  most  trypanosomiasis,  Mai  de  Caderas  is 
found  in  swam]n-  localities.  In  infected  districts  in  Argentine 
the  disease  plays  havoc  with  the  horse  industry. 

Etiology. — The  cause  of  Mai  de  Caderas  is  the  Try|)ano- 
soma  equinum  (T.  elmassiana),  which  is  very  similar  to  the 
Trypanosoma  brucei  of  nagana. 

The  mode  of  transmission  of  the  disease  from  animal  to 
animal  is  as  yet  unsolved.  Formerly  horse  flies  (Stomoxys 
brava),  tabanidea  and  even  mosquitoes  were  accused. 

Doubt  has  been  cast  upon  this  assumption  by  the  fact 
that  a  wire  fence  is  sufficient  to  prevent  the  spread  of  the 
disease.  It  is  proba])le  that  the  disease  is  transmitted 
indirectly  by  the  cajjybara  (a  large  rodent).  The  capybaras 
are  said  to  die  in  great  numbers  and  are  eaten  by  dogs,  from 
wliich  a  spread  to  horses  is  assumerl. 

Symptoms. — The  ])eriod  of  incubation  is  about  ten  days. 
The  most  j)r()minent  symi)tom  is  weakness  of  the  hind  parts, 
loss  of  cofirdination,  the  hindlegs  being  dragged  and  the 
fetlocks  knuckling  over  when  walking.     The  patient  rapidly 

••  Mill  do  Cadi'ias,  "hip  diseasi',"  fnjiii  a  iir.iiiiiiuMit  symptom. 


COCCI  DIOSI^  459 

emaciates  and  becomes  so  weak  (i)arai)aresis)  that  when 
down  they  rise  from  the  ground  with  great  difficulty.  When 
standing  the  hmbs  are  spread  apart.  Finally  the  patients 
remain  down,  show  paralysis  of  the  rectum  (fecal  stasis), 
relaxation  of  the  anal  sphincter,  and  incontinence  of  feces. 
The  fever  is  atypical,  urticaria-like  swellings  appear  on  the 
skin,  and  individual  joints  become  swollen.  Edemas  of 
pendent  parts  of  the  body  are  not  so  common  as  in  surra 
and  nagana.  Albuminuria  and  hematuria  are  not  rare. 
Conjunctivitis  and  keratitis  are  common  complications. 
The  appetite  is  retained  to  the  end.  In  acute  cases  the 
trypanosomes  are  found  in  the  blood  in  numbers ;  in  chronic 
cases  their  determination  is  only  possible  by  inoculation  of 
rats  and  mice. 

Course. — The  course  is  usually  one  or  two  months;  chronic 
cases  may  linger  for  months,  the  emaciation  and  paresis 
developing  very  gradually. 

Prognosis. — Bad.     Nearly  all  cases  die. 

Treatment. — No  medicinal  treatment  is  of  value.  Trypan- 
roth  has  been  tried  in  experimental  animals  (mice)  with  some 
success. 

Prevention. — As  a  mode  of  transmission  is  still  in  doubt, 
well  directed  preventive  measures  are  wanting.  Keeping 
susceptible  horses  off  low-lying  undrained  fields  and  killing 
the  diseased  animals  are  recommended. 


COCCIDIOSIS. 

CocciDiAL  DyseiVtery  OF  Cattle.     Red  Dysentery. 

Definition. — An  inflammation  of  the  intestines  of  cattle 
due  to  a  coccidium  and  characterized  by  a  bloody  diarrhea. 

Occurrence. — The  disease  is  found  principally  among 
young  cattle  on  pasture,  especially  in  wet  seasons  and  during 
the  months  of  June  to  September.  As  the  disease  assumes 
an  enzootic  or  sometimes  an  epizootic  form,  afi'ecting  a  large 
number  of  animals,  and  is  not  infrequently  fatal,  it  assumes 
economic  importance. 


4()()        INFECTIOUS  DISEASES  DUE  TO  PROTOZOA 

Etiology. — Tlie  cause  is  the  C'occidium  zueriii,  wliidi  is 
foiuid  in  the  ieces  of  sick  animals  as  round  or  oval  protozoa, 
varying  in  length  from  10  to  25  microns.  lender  the  micro- 
scope they  are  highly  light  refractive  and  unstained  apjjcar 
greenish-violet  in  color. 

Natural  Infection. — Infection  takes  j)lace  through  the 
digesti\'e  tract,  tlie  coccidia  being  taken  up  with  water  from 
pools  and  swamjis  and  also  probably  with  infested  food. 
Occasionally  infection  occurs  in  barns,  especially  when  damp 
and  dirty.  Young  animals  are  much  more  susceptible  than 
older  ones  which,  however,  are  by  no  means  immune.  The 
disease  is  rarely  seen  in  calves  under  six  months,  as  they 
are  seldom  exposed  to  infested  pastures.  Cattle  ranging 
from  six  months  to  two  years  of  age  are  most  often  attacked. 

Necropsy. — The  lesions  are  usually  confined  to  the  large 
bowel,  cs])C('ially  its  ])osterior  ])ortion.  The  mucosa  is 
swollen,  congested,  often  thrown  into  transverse  folds  (cor- 
rugated), i)artially  denuded  of  its  epithelium,  and  spotted 
with  hemorrliages.  Frequently  masses  of  adherent  epithe- 
lium hang  in  shreds  from  the  eroded  mucous  membrane. 
The  contents  are  a  thin  fluid,  and  vary  in  color  from  greenish 
to  reddish  gray  or  reddish  brown.  Sometimes  blood-clots 
are  mixed  with  them.  Over  the  mucosa  a  yellowish  or  grayish 
fibrinous  exudate  is  often  noted.  Due  to  secondary  infection, 
the  Small  intestines  may  show  hemorrhagic  inflammation 
or  even  necrosis.  In  the  intestinal  contents  and  mucosa 
(especially  in  the  loose  shreds)  lunubers  of  coccidia  are  found. 
The  cadaver  is  usually  anemic  and  emaciated. 

Symptoms. — The  period  of  incubation  varies  from  one  to 
three  weeks.  A  number  of  young  cattle  on  pasture  may  be 
simultaneously  att'ected;  more  rarely  a  whole  herd  may 
develop  symptoms  in  a  single  day.  The  principal  symptom 
is  a  suddenly  appearing  diarrhea,  the  feces  thin,  copious, 
discharged  with  considerable  tenesmus,  and  after  a  few  hours 
streaked  with  blood.  If  tlie  tenesmus  is  severe,  i)rolapse  of 
the  rectum  may  result.  In  adult  cattle  the  symi)toms' 
disappear  in  three  or  four  days,  and  after  showing  capricious 
api)etite  for  a  time,  recovery  follows.  In  young  animals, 
however,  the  condition  gets  worse,  the  feces  becoming  very 


COCCIDIOSIS  461 

fetid,  admixed  with  clots  and  shreds  of  mucus— often  ichorous 
in  character.  The  patients  are  greatly  depressed,  have  no 
appetite,  rapidly  emaciate,  and  show  an  uncertain,  staggering 
gait.  The  pulse  becomes  increased  and  the  temperature 
elevated.     Death  may  occur  within  one  to  three  days. 

Diagnosis.— The  occurrence  of  the  disease  among  young 
stock  on  pasture,  its  acute  course  and  the  foul  hemorrhagic 
diarrhea  with  rapid  emaciation  of  the  patient  are  very 
suggestive.  The  determination  of  the  coccidia  by  micro- 
scopic examination  of  the  feces  clinches  the  diagnosis. 

Course  and  Prognosis.— The  course  is  acute,  lasting  from 
one  to  ten  days.  Animals  which  recover  do  so  very  gradually. 
Individual  patients  are  left  with  a  profound  anemia  which 
may  lead  to  death  in  a  few  months.  IMild  cases  which 
assume  the  t>T)e  of  a  simple  gastro-intestinal  catarrh  recover 
promptly  in  eighteen  to  twenty-four  hours.  The  prognosis 
in  young  animals  is  less  favorable  than  in  older  ones.  Ob- 
viously weak  and  debilitated  patients  succumb  more  rapidly 
than  those  with  higher  resistance.  The  mortality  is  about 
5  to  10  per  cent. 

Treatment.— Treatment  is  only  successful  in  mild  cases. 
It  is  unportant  to  take  the  animals  from  the  pasture  and 
place  them  on  dry  feed  in  the  stable  where  they  should  be 
provided  with  pure  water.  Internally  intestinal  disinfectants 
and  astringents  have  been  recommended.  A  mixture  of 
tincture  of  opimn  (oij),  oil  of  eucalyptus  (gss),  dilute  acetic 
acid  (5ss),  mixed  with  water  as  a  drench,  is  recommended. 
The  above  dose  may  be  given  hourly  until  the  symptoms 
begin  to  subside,  afterward  three  times  daily.  Intrarectal 
injections  of  tannic  acid  (1  per  cent.)  or  alum  (1  per  cent.) 
have  given  good  results.  As  the  appetite  remains  impaired 
for  some  time  the  patient  may  be  fed  milk  and  eggs  as  a 
substitute  for  its  usual  food. 

Prevention.-Prevention  consists  in  keeping  young  cattle 
away  from  the  polluted  water  of  swamps  and  stagnant 
pools.  Once  the  disease  breaks  out  the  cattle  should  be 
removed  to  the  stable  and  placed  on  dry  feed  with  pure 
water,  oi  at  least  to  dry  pastures  provided  with  a  pure  water 
supply.  The  coccidia  in  the  feces  are  killed  with  a  3  per  cent, 
solution  of  sulphuric  acid. 


INDEX. 


Abortion,  infectious,  430 
course.  434 
definition,  430 
diagnosis,  433,  434 
etiologj',  431 
in  cows,  431 
in  mares,  431 
natural  infection,  431,  432 
necropsy,  433 
occurrence,  430,  431 
prevention,  435,  436 

immunization,  435,  436 
symptoms,  432,  433 
treatment,  434,  435 
Abscess  of  brain,  223 
of  liver,  146 
of  lungs,  45 
Acne,  258 

contagious,  267 
definition,  258 
treatment,  258 
Actinomycosis,  413 
course,  417 
definition,  413,  414 
diagnosis,  416,  417 
etiology,  414 

natural  infection,  414,  415 
occurrence,  414 
prognosis,  417 

sjTnptoms  in  cattle,  415,  416 
head,  415 
lips.  416 
pharynx.  416 
tongue,  415,  416 
treatment,  417 
African  horse  sickness,  337 
definition,  337 
etiology,  337 
natural  infection,  337 


African   horse   sickness,   necropsy, 
337,  338 
occurrence,  337 
prevention.  338 
svmptoms,  338 
"  acute,  338 
peracute,  338 
subacute,  3.38 
treatment,  338 
Allotriophagy,  187 
Alopecia,  256 
areata,  256 
definition,  256 
diagnosis.  257 
etiology.  256 
symptomatica.  256 
symptoms,  256,  257 
treatment,  257 
Alveolar  emphysema,  chronic.  46 
Amyloid  kidney.  207 

liver,  151 
Anemia,  169 

of  brain  and  its  membranes,  211 
course,  170 
definition,  169 
etiology,  169 
infectious,  of  horse,  174 
course,  178 
definition,  174 
diagnosis,  178 
etiology,  175 
natural  infection,  175 
necropsy,  175,  176 
occurrence,  174,  175 
prognosis,  178 
prophylaxis,  179 
symptoms,  176,  177,  178 
treatment,  178 
prognosis,  170 
symptoms,  169,  170 
treatment,  170 


4G4 


INDEX 


Aneurysm  of  aorta,  80,  81 
Angina  simplex,  89 
Anthrax,  279 

classification,  282 
acute,  282 
cutaneous,  282,  283 
peracute,  282 
subacute,  282 

course,  283 

definition,  279 

diagnosis,  283 

etiology,  279 

natural  infection,  280 
digestive  tract,  280 
respiratory  tract,  280 
skin,  280 

necropsy,  281 

occurrence,  279 

prevention,  284,  285 

prognosis,  284 

symptoms,  281,  282,  283 
period  of  incubation,  282 

treatment,  284 
Aorta,  aneurysm  of,  80,  81 
Apoplexy,  216 

definition,  216 

diagnosis,  217 

etiology,  216 

symptoms,  216,  217 

treatment,  217 
Arhythmia  cordis,  74 
Arthritis,  pyemic,  308 
Articular  rheumatism,  194 
Ascarides,  135 
Ascites,  155 
Azoturia,  179 

complications,  181         • 

course,  181 

(lefiniti(m,  179 

diagnosis,  181,  182 

etiology,  179,  180 

occurrence,  179 

prognosis,  182 

proi)hylaxis,  183 

symptoms,  180,  181 

treatment,  182,  183 


B 

BiGHEAD  of  sheej),  275 
definition,  275 
etiology,  276 
occurrence,  275,  276 


Bighead  of  sheep,  ])roph\laxi.s,  277 
symptoms,  276 
treatment,  277 
Biliary  fever,  449 
Black-leg,  287 
course,  289 
•  definition,  287 
diagnosis,  289 
etiology,  287,  288 
natural  infection,  288 
necropsy,  289 
occurrence,  287 
prognosis,  289 
prophylaxis,  290 
symptoms,  288,  289 
general,  288 
local,  288 
treatment,  289 
Bleeding  from  lungs,  43 
Bloating  in  ox,  97 
course,  98 
definition,  97 
diagnosis,  98 
etiology,  97,  98 
occurrence,  97 
prognosis,  98 
prophylaxis,  100 
symptoms,  98 
treatment,  98,  99 
Borna  disease,  225 
course,  226 
definition,  225 
etiology,  225 

natural  infection,  225,  226 
necropsy,  226 
occurrence,  225 
prognosis,  226 
symi)toms,  226 
treatment,  226 
Bots,  132 
Bradycardia,  74 
Brain,  209,  210 

and  its  membranes,  211 
anemia  of,  211 
etiology,  211 
prognosis,  211 
symptoms,  211 
treatment,  211,  212 
congestion  of,  212 
course,  213 
diagnosis,  213 
etiology,  212 
symptoms,  212 
treatment,  213 


INDEX 


465 


Brain  and  its   membranes,  hemor- 
rhage of,  216 
inflammation  of,  221 
symptoms,  209 

focal  or  topical,  210 
general,  209 
traumatic  injury  and  concussion 
of,  214 
definition,  214 
diagnosis,  215 
etiology,  214  _ 
prognosis,  215 
symptoms,  214,  215 
treatment,  215 
tumors  in,  228,  229 
diagnosis,  229 
symptoms,  229 
treatment,  229 
Braxy,  290 
course,  292 
definition,  290 
diagnosis,  292 
etiology,  291 
natural  infection,  291 
necropsy,  291 
occurrence,  290,  291 
prognosis,  292 
symptoms,  291,  292 
treatment,  292 

protective  inoculation,  292 
Broken  back,  234 

neck,  234 
Bronchitis,  catarrhal,  35 
chronic,  36 
course,  37 
definition,  35 
diagnosis,  37 
etiology,  35 
forms,  35 
occurrence,  35 
prognosis,  37 
symptoms,  36,  37 
treatment,  37,  38 
verminous,  38 
definition,  38 
diagnosis,  40 
etiology,  39 
necropsy,  39 
occurrence,  38 
prognosis,  40 
prophylaxis,  40 
symptoms,  39,  40 
treatment,  40 
Bronchopneumonia,  54,  296 

30 


Bronchopneumonia,      cheesy,      of 

sheep,  412  ,  ^o 

Bronchopulmonary  hemorrhage,  i6 
Bronchorrhagia,  43 


Calf  diphtheria,  36^ 
Canine  madness,  382 
Carcinoma  of  liver,  151 
Caseous   lymphadenitis    of    sheep, 

412 
Catalepsy,  246  .     ,   ^, 

Catarrh,  gastro-intestmal,  94 
of  horse,  94 
course,  94 
definition,  94 
j  etiology,  94,  95 

I  occurrence,  94 

I  prognosis,  96 

symptoms,  95,  96 
gastric,  95 
I  intestinal,  95,  96 

treatment,  96,  97 
of  ox,  114 
course,  117 
definition,  114,  115 
diagnosis,  116,  117 
I  etiology,  115 

occurrerice,  115 
I  prognosis,  117 

symptoms,  115,  116 
gastric,  115,  116 
general,  116 
intestinal,  116 
treatment,  117,  118 
hygienic,  117 
medicinal,  117,  118 
of  sucklings,  118 
course,  119,  120 
definition,  118 
diagnosis,  119 
etiology,  118,  119 
occurrence,  118 
prognosis,  119,  120 
symptoms,  119 
treatment,  120 
of  guttural  pouches,  27 
maUgnant  head,  of  ox,  366 
course,  368 
definition,  360 
etiology,  366 
natural  infection,  366,  367 


466 


INDEX 


Catarrh,    malignant  head,   of   ox, 
occurrence,  366 
prognosis,  368 
symptoms,  367,  368 
digestive  tract,  368 
eyes,  367 
nerves,  367 
respiratory  tract,  367 
skin,  368 
udder,  368 
treatment,  368,  369 
of  maxillarv  and  frontal  sinuses, 

26 
nasal,  17 
Catarrhal  fever,  313 
Cattle  plague,  333 
Cestodes,  133 
Chest  plague,  319 
Chicken  lice,  270 
CholeHthiasis,  151 
Chorea,  247 
definition,  247 
etiology,  247 
Cirrhosis  of  liver,  145 
Coccidial  dysentery  of  cattle,  459 
Coccidiosis,  459 
course,  461 
definition,  459 
diagnosis,  461 
etiology,  460 
natural  infection,  460 
necropsy,  460 
occurrence,  459 
prevention,  461 
prognosis,  461 
symptoms,  460,  461 
treatment,  461 
Ctt'nurosis,  229 
Coital  exanthema,  355 
Colics,  so-called,  of  horse,  101 
etiology,  102,  103 
exciting,  102,  103 
predisposing,  102 
anatomical,  102 
pathological,  102 
forms,  103 

acute   dilatation   of   stomach, 
103 
course,  105 
definiticm,  103 
diagnosis,  104,  105 
occurrence,  103,  104 
treatment,  105,  106 
embolic.  111 


Colics,   forms,   embolic,  definition, 
111,  112 
diagnosis,  113 
pathogenesis,  112 
symptoms,  112,  113 
treatment,  113 
flatulent,  114 
symptoms,  114 
treatment,  114 
impaction  with  abnormal  dis- 
placement, 110 
forms,  110 

displacement      of      large 
bowel,  110 
of  small  bowel,  111 
simple  impaction  of  intestines, 
106 
covH'se,  107 
definition,  106 
etiology,  106 
forms,  106 

impaction  of  large  bowel, 
108 
of  cecum,  108 
of  colon,  109,  110 
of  small  bowel,  106,  107 
occurrence,  106 
prognosis,  107 
treatment,  107,  108 
spasmodic,  1 13 
definition,  113 
treatment,  113 
worm,  113,  114 
treatment,  114 
statistics,  103 
morbidity,  103 
mortality,  103 
Colpitis   granulosa    infectiosa    bo- 

vum,  436 
Compsomyia  maceUaria,  270 
Congestion  of  brain  and  its  mem- 
branes, 212 
of  kidneys,  206 
of  lungs,  41 
Consumption,  389 
Contagious  acne,  267 

stomatitis  of  horse,  352 
Cornstalk  disease,  296 
Coryza,  acute,  17 

contagiosa  cciuorum,  358 
gangrenosa  IwAiim,  366 
gangrenous,  366 
pvistulous,  21 
C'OW-pox,  343 


INDEX 


467 


CrjiJtogamic  poisoning,  125 
Cystic  kidney,  207 
Cysticercus  celliilosse,  197 
inermis,  198 


Demodex  folliculorum  (var.  suis), 

265 
Derman3-ssus  a\'ium,  270 
Dermatitis,   contagious  pustulous, 
267 
definition,  267 
diagnosis,  268 
etiology-,  267 
sjTnptonxs,  267,  268 
treatment,  268 
Diabetes,  185 
definition,  185 
insipidus,  185 
mellitus,  186 
course,  186 
definition,  186 
etiologj-,  186 
occurrence,  186 
sj-mptoms,  186 
treatment,  186 
Diaphragm,  spasms  of,  247 
course,  248 
definition,  247 
diagnosis,  248 
etiology,  247 
occurrence,  247 
prognosis,  248 
symptoms,  247,  248 
treatment,  248 
Diphtheria,  calf,  369 
Distemper,  loin,  174 
Distomatosis,  147 
Dochmiasis,  141 
Dourine,  451 
course,  455 
definition,  451 
diagnosis,  454,  455 
etiolog>',  451 

natural  infection,  451,  452 
occurrence,  451 
prognosis,  455 
symptoms,  452,  453,  454 

nervous,  453,  454 
treatment,  455,  456 
Dysenteria  neonatorum,  305 
Dysentery,  chronic  bacterial,  410 
coccidial,  of  cattle,  459 


Dj'sentery,  red,  459 
sporadic,  118 
of  suckhngs,  305 

course,  307 

definition,  305 

diagnosis,  306 

etiologA^  305 

natural  infection,  305,  306 

occurrence,  305 

prognosis,  307 

symptoms,  306 

treatment,  307,  308 


East  African  coast  fever,  448 
definition,  448 
etiolog\',  448,  449 
occurrence,  448 
prognosis,  449 
prophylaxis,  449 
symptoms.  449 
Echinococcus  disease  of  Uver,  148 
definition,  148 
natural  history,  148,  149 
occurrence,  148 
symptoms,  149 
treatment,  149,  150 
Echinorhynchus  gigas,  140 
Eclampsia,  246 
Eczema,  249 
acute,  253 

treatment,  253,  254 
chronic,  254 

treatment,  254 
course,  249 
definition,  249 
etiology',  250 
forms,  249 
crustated,  249 
erj'thematous,  249 
impetiginous,  249 
madidans,  249 
papulous,  249 
pustulous,  249 
red  or  weeping,  249 
seborrheic,  250 
squamate,  250 
sj'cosiform,  250 
vesicular,  249 
of  horse,  251 
of  ox,  251 
of  swine,  252 


468 


INDEX 


Ecz;>ma,  prognosis,  252 
in  swine,  252 
symptoms,  250 
in  horse,  251 
in  ox,  251,  252 
treatment,  252,  253 
Edema  of  glottis,  31 
malignant,  285 
course,  287 
definition,  285 
diagnosis,  286 
etiology,  285 

natural  infection,  285,  286 
occurrence,  285 
prognosis,  287 
symptoms,  286 
treatment,  287 
pulmonary,  41 
course,  42 
definition,  41 
diagnosis,  42 
etiology,  42 
prognosis,  42 
symptoms,  42 
treatment,  42,  43 
Electric  stroke,  215 
Embolic  colic,  111 
Emphysema,  acute  interstitial  pul- 
monary, 48 
course,  49 
definition,  48 
diagnosis,  49 
etiology,  49 
occurrence,  48 
symptoms,  49 
treatment,  49 
chronic  alveolar,  46 
course,  47 
definition,  46 
diagnosis,  47,  48 
drugs,  48 
etiology,  46 
occurrence,  46 
prognosis,  48 
symptoms,  46,  47 
treatment,  48 
Encephalitis,  221 
definition,  221 
meningo-,  217 
non-sui)i)urative,  222 
course,  222 
definition,  221 
diagnosis,  223 
etiology,  221 


Encephalitis,         non-suppurative, 
occurrence,  221 

symptoms,  222 

treatment,  223 
suppurative,  223 

diagnosis,  224 

etiology,  223,  224 

symptoms,  224 

treatment,  225 
Endocarditis,  77 
acute,  77,  78 

thlTerential  diagnosis,  78 

symptoms,  78 

treatment,  78,  79 
chronic,  79 

etiology,  79 

general  symptoms,  79,  80 

individual  valvular  and  ostial 
defects,  SO 

treatment,  80 
Enteritis,  croupous,  124 

course,  125 

definition,  124 

diagnosis,  125 

etiology,  124 

occurrence,  124 

prognosis,  125 

symptoms,  124,  125 

treatment,  125 
membranous,  124 
specific  chronic,  of  ox,  410 
Enzootic  jiaraplegia,  242 
Ejiileps}',  245 
definition,  245 
etiology,  245 
occurrence,  245 
symptoms,  245,  246 

grand  mal,  245,  246 

petit  mal,  246 
treatment,  246 
Epistaxis,  22 
definition,  22 
diagnosis,  23 
etiology,  22 
symptoms,  22 
treatment,  23 
Epizootic  lymphangitis,  427 
Erj'sipelas,  swine,  292 

definition,  292 

diagnosis.  294,  295 

etiology,  293 

natural  infection,  293 

necrojisy,  293 

occurrence,  292 


INDEX 


469 


Erj'sipelas,  swine,  prevention,  295 
protective  inoculation,  295 
prognosis,  294 
symptoms,  293,  294 
chronic  form,  293,  294 
septicemic  form,  294 
skin  form,  293,  294 
treatment,  295 
Erythema,  257 
Eustrongylus  gigas,  208 
Exanthema,  coital,  355 
course,  357 
definition,  355 
diagnosis,  357 
etiology,  355 

natural  infection,  355,  356 
occuiTcnce,  355 
symptoms,  356,  357 
treatment,  337 


Falling  sickness,  245 

Favus,  267 

Fibrinous  pneumonia,  infectious,  of 

horse,  319 
Filaria,  skin,  271 
varieties,  271 

hemorrhagica,  271 
irritans,  271 
Flatulent  colic,  114 
FoUicle  mite,  259 
Foot-and-mouth  disease,  345 
course,  350,  351 
definition,  345,  346 
diagnosis,  349,  350 

confused  with  ergotism,  350 
with  foot-rot  of  sheep,  350 
with   mycotic   stomatitis, 

349 
■with  necrotic   stomatitis, 

350 
with  traumatic  stomatitis, 
349 
etiology,  346 

natural  infection,  346,  347 
occurrence,  346 
prognosis,  351 
symptoms,  347,  348,  349 
treatment,  351,  352 

protective        inoculation, 
352 
Forage  poisoning,  125 


G 


Gall-stones,  151 
diagnosis,  151 
sj'mptoms,  151 
treatment,  151 
Game  and  cattle  plague,  296 
Gangrene,  pulmonary,  44 
definition,  44 
diagnosis,  45 
etiology,  44 
occurrence,  44 
prognosis,  45 
s.ymptoms,  44 
treatment,  45 
Gastrectasis,  103 
Gastritis,  traumatic,  128 
course,  131 
definition,  128 
diagnosis,  130,  131 
etiology,  129 
occurrence,  128,  129 
prognosis,  131 
symptoms,  129,  130 
treatment,  131,  132 
Gastro-enteritis,  120 
definition,  120,  121 
forms,  121 
catarrhal,  94 
mj'cotic,  125 
course,  127 
definition,  125 
diagnosis,  127 
etiology,  126 
occurrence,  125,  126 
prognosis,  127 
sjanptoms,  126 

gastro-intestinal,  126 
general,  127 
nervous,  126 
treatment,  127 
medicinal,  128 
simple,  121 
course,  123 
diagnosis,  122,  123 
etiology,  121,  122 
prognosis,  123 
sj'mptoms,  122 
treatment,  123,  124 
occurrence,  121 
toxic,  128 
Gastro-intestinal  catarrh  of  horse, 
94 
of  ox,  114 


470 


INDEX 


Gastro-intestinal  catarrh  of  suck- 
lings, 118 
Gastromycosis  ovis,  290 
Gastrophilus,  132 
life  history,  132,  133 
prophylaxis,  133 
treatment,  133 
varieties,  132 
Genital  horse-pox,  355 
Gid,  229 

definition,  229 
natural  history,  230 
occurrence,  230 
symptoms  in  sheep,  230,  231 
treatment  in  sheep,  231 
Glanders,  417 
course,  426,  427 
definition,  417,  41cS 
diagnosis,  422,  423 
differential  diagnosis,  423 
agglutination,  425 
complement-fixation,      425, 

426 
inoculations,  426 
mallein  test,  423,  424,  425 
interpretation   of  results, 
424 
etiology,  418 
nasal,  420,421 
natural  infection,  418,  419 
occurrence,  418 
pulmonary,  421,  422 
skin,  421 

symptoms,  419,  420,  421,  422 
Glottis,  edema  of,  31 
Gout,  186 
Granular    vaginitis,    infectious,  of 

cattle,  436 
Grub  in  head  of  sheep,  24 
definition,  24 
diagnosis,  25,  26 
etiology,  24 
occurrence,  24 
prevention,  26 
symptoms,  25 
treatment,  26 
Guttural  pouches,  catarrh  of,  27 
definition,  27 
etiology,  27 
symptoms,  27 
treatment,  27 
tympany  of,  27 
definition,  27 
etiologjf,  27 


Guttural    pouches,     tympany    of, 
occurrence,  27 
symptoms,  27 
treatment,  27 


H 


Heart  beat,  intermittent,  74 
course,  75 
definition,  74 
etiology,  74 
symptoms,  74,  75 
treatment,  75 
hypertrophy  and  dilatation  of,  75 
course,  76 
definition,  75 
diagnosis,  76 
etiology,  75 
symptoms,  75,  76 
treatment,  76 
nervous  palpitation  of,  73 
course,  73 
defi.nition,  73 
diagnosis,  73 
etiology,  73 
occurrence,  73 
Hymi)toms,  73 
treatment,  73 
rui)ture  of,  80 
slow,  74 

definition,  74 
diagnosis,  74 
etiology,  74 
symptoms,  74 
treatment,  74 
tumors  in,  81 
Heartwater,  338 
Heatstroke,  213 
prognosis,  214 
symptoms,  213,  214 
treatment,  214 
Helminthiasis,  132 
Hematopinus,  269 
Hematuria,  208 
Hemoglobinuria,  208 
infectious,  of  ox,  446 
paralytic,  179 
Hemopericardium,  72 
definition,  72 
etiologj',  72 
symptoms,  72 
Hemophilia,  173 
definition,  173 


INDEX 


471 


Hemophilia,  etiology,  173 
Hemoptysis,  43 

Hemorrhage  in  brain  and  its  mem- 
branes, 216 
bronchopulmonary,  43 
definition,  43 
etiolog}',  43 
sj'mptoms,  43 
treatment,  43 
renal,  206 

etiology,  206,  207 
sj'mptoms,  207 
Hemorrhagic  septicemia,  295 
of  cattle,  296 
com*se,  299 
definition,  296 
differential  diagnosis,  298 
etiology,  296 
natural  infection,  297 
necropsy,  297 
occurrence,  296 
prognosis,  299 
symptoms,  297,  298 

exanthematous  form,  298 
intestinal  form.  297,  298 
pectoral  form,  298 
treatment,  299 
of  sheep,  300 
definition,  300 
diagnosis.  302,  303 
etiology-,  300 

natural  infection,  300,  301 
necropsy,  301.  302 
occurrence,  300 
prevention,  303 
symptoms,  302 
treatment,  303 

protective  inoculation, 
303 
Hepatitis,  144 

acute  parenchj'matous,  144 
definition,  144 
diagnosis,  145 
etiologj',  144,  145 
necropsy,  145 
s^Tnptoms,  145 
treatment,  145 
chronic  interstitial,  145 
course,  146 
definition,  145 
etiolog>',  145 
occiu-rence,  145 
sjTnptoms,  146 
treatment,  146 


Hepatitis,  purulent,  146 
course.  146 
etiology,  146 
prognosis,  146 
symptoms,  146 
treatment,  146 
Herpes,  265 
in  cattle,  266 
definition,  265 
diagnosis,  266 
etiology,  265,  266 
forms,  266 

circinatus,  265 
maculosis,  266 
tonsurans,  266 
vesiculosis,  266 
in  horse,  327 
occm'rence,  265 
treatment,  267 
Hodgkin's  disease,  172 
Hog  cholera,  327 
definition,  327 
diagnosis,  331,  332 

confused  with  lung-worms, 
332 
with  swill  cholera,  332 
with  tuberculosis,  332 
etiology,  328 

natural  infection,  328,  329 
necropsy,  329,  330 
intestinal  form.  329 
pectoral  form,  329 
septicemic  form,  329 
occurrence.  327,  328 
prognosis,  332 
svmptoms,  330.  331 
bowel  form,  330,  331 
mixed  form,  331 
pectoral  form,  331 
septicemic  form.  330 
treatment,  333 
measles,  197 
definition,  197 
symptoms,  197 
Horse-pox,  345 
genital.  355 
Hydremia.  173 
definition.  173 
etiologj-.  173 
Hydrocephalus,  chronic,  227 
course,  228 
definition,  227 
etiology,  227 
prognosis,  228 


472 


INDEX 


Hydrocephalus,     chronic,      symp- 
toms, 227,  228 
treatment,  228 
Hydronephrosis,  207 
etiolofiy,  207 
symptoms,  207 
treatment,  207 
Hydropericanhum,  71 
definition,  71 
(Hafinosis,  72 
etiology,  71 
s3'ni])toms,  71 
treatment,  72 
Hydrophobia,  382 
Hydropsy,  abdominal,  155 
definition,  155 
diagnosis,  156 
etiology,  155 
occmrence,  155 
prognosis,  156 
symptoms,  155,  156 
treatment,  156,  157 
Hj'drothorax,  66 
definition,  66 
diagnosis,  66 
etiology,  66 
symptoms,  66 
treatment,  66 
Hyperemia,  206 
definition,  206 
diagnosis,  206 
symi)tonis,  206 
treatment,  206 
Hj'perkinesis  cordis,  73 
Hypertrophy    and     dilatation     of 

heart,  75 
Hypoderma  lincatum,  268 


Icterus,  142 

gravis,  143 

neonatorum,  143 
Impaction  of  cecum,  108 

of  colon,  109 

of  intestines,  106 

of  large  bowel,  108 

of  small  bowel,  106,  107 
Impotency,  167 

definition,  167 

etiology,  167 

treatment,  167 
Indigestidn  of  cattle,  1 14 

traumatic,  of  ox,  128 


Infectious  aljortion,  430 
filirinous    pneumonia    of    horse 

319 
hemoglobinuria  of  ox,  446 
itching  disease,  231 
Influenza  of  horse,  313 
course,  317 
definition,  313 
diagnosis,  316,  317 
etiology,  314 

natural  infection,  314,  315 
occurrence,  313,  314 
prognosis,  317 
symptoms,  315,  316 

digestive  tract,  315,  316 
eye  lesions,  315 
respiratory  tract,  315 
skin,  316 

urinogenital  tract,  316 
treatment,  317,  318,  319 
pectoral,  319 
Intestines,  animal  parasites  in,  133 
varieties,  133 

echinorhynchus  gigas,  140 
crsoi)hagostoma,  138 
oxyuris  curvula,  140 
palisade- worms,  136 
round-worms,  135 
tapeworms,  133 
uncinaria,  141 
whip-worms,  141 
simple  impaction  of,  106 
Itching  disease,  infectious,  231 
Ixodoidea,  270 


Japanese  farcy,  427 
Jaundice,  142 

malignant,  143 
definition,  143 
etiology,  143 
occurrence,  143 
])rognosis,  143 
symptoms,  143 
treatment,  143 

of  newl)orn,  143 
definition,  143 
etiology,  144 
occurrence,  144 
prognosis,  144 
■symptoms,  144 
treatment,  144 

obstructive,  142 


INDEX 


473 


Jaundice,    obstructive,    definition, 
142 

prognosis,  143 

symptoms,  142,  143 

treatment,  143 
Johne's  disease,  410 

com'se,  412 

definition,  410 

diagnosis,  411 

etiology,  410 

natural  infection,  410 

necropsy,  410,  411 

occurrence,  410 

prognosis,  412 

symptoms,  411 

treatment,  412 
Joint  ill,  308 


KiDXEY,  amj^loid,  207 
congestion  of,  208 
cystic,  207 
inflammation  of,  199 
parasites  in,  208 
stones,  204 
tumors  in,  207 
treatment,  207 


Laryngitis,  28 
forms,  28 
catarrhal,  28 

course,  29 

definition,  28 

diagnosis,  29 

etiology,  28 

occurrence,  28 

symptoms,  28,  29 

treatment,  29,  30 
croupous,  30  » 

course,  31 

definition,  30 

diagnosis,  31 

etiology,  30 

occurrence,  30 

symptoms,  31 

treatment,  31 
edematous,  31 

definition,  31,  32 
inflammatory,  32 
non-inflammatory,  32 


prognosis,  32 


Laryngitis,      forms,       ed?matous, 
symptoms,  32 
treatment,  32 
membranous,  30 
Larynx,  tumors  in,  34 
occurrence,  34 
symptoms,  34 
Leukemia,  170 
definition,  170 
diagnosis,  172 
etiology,  170 
forms,  170,  171 
prognosis,  172 
symptoms,  171,  172 
treatment,  172 
Leuko-encephaUtis,  125 
Lice,  269 

causing  ostitis  in  ox,  270 
chicken,  270 
definition,  269 
treatment,  269 
Licking  disease,  187 
course,  187,  188 
definition,  187 
etiology,  187 
occurrence,  187 
prevention,  188 
prognosis,  187,  188 
symptoms,  187 
treatment,  188 
Lightning  stroke,  215 
occurrence,  215 
symptoms,  216 
treatment,  216 
Lip-and-leg  ulceration  of  sheep,  272 
definition,  272 
etiology,  272 
occurrence,  272 
prophylaxis,  275 
symptoms,  272,  273,  274 
foot-rot  form,  273 
lip-and-leg  form,  272 
sore  mouth  form,  273 
venereal  form,  273 
treatment,  274,  275 
Liver,  abscess  of,  146 
amyloid,  151 
character,  151 
symptoms,  151 
carcinoma  of,  151 
cirrhosis  of,  145 
echinococcus  disease  of,  148 
fluke  disease,  147 
course,  148 


474 


INDEX 


Liver  fluke  disease,  definition,  147 
natural  history,  147 
occurrence,  147 
prophylaxis,  148 
symptoms,  14S 
treatment,  148 
inflammation  of,  144 
necrosis  of,  150 
parasites  in,  151 
rupture  of,  150 
definition,  150 
etiology,  150 
symptoms,  150 
treatment,  150 
Lockjaw,  '.MiS 
Loin  distemy)er,  174 
Lump  jaw,  413        ' 
Lung  fever,  49 

plague  of  cattle,  371 
course,  375 
definition,  371 
diagnosis,  374,  375 
from    hemorrhagic    septi- 
cemia, 374 
from  pneumomycosis,  374, 

375 
from  pulmonary  tubercu- 
losis, 374 
from  verminousbronchit  is, 
375 
etiology,  372 
natural  infection,  372 
necropsy,  372,  373 
occurrence,  371,  372 
symptoms,  373,  374 
treatment,  375 
worm  plague,  38 
Lungs,  abscess  of,  45 
course,  45 
definition,  45 
diagnosis,  45 
etiology,  45 
symptoms,  45 
treatment,  45 
bleeding  from,  43 
circulatory  disturbances  in,  41 
congestion  of,  41 
definition,  41 
etiology,  41 
inflammation  of,  49 
tumors  in,  60 
Lymphadenitis,  caseous,  of  sheep, 
412 
course,  413 


Lymphadenitis,  caseous,  of  sheep, 
definition,  412 

etiology,  412 

natural  infection,  412 

necropsy,  412,  413 

occurrence,  412 

prognosis,  413 

symptoms,  413 

treatment,  413 
Lymphangitis,  epizootic,  427 
course,  428 
definition,  427 
diagnosis,  428 
etiology,  427 

natural  infection,  427,  428 
occurrence,  427 
prophylaxis,  429 
symptoms,  428 
treatment,  428,  429 
ulcerous,  of  horse,  429 
definition,  429 
diagnosis,  430 
etiology,  429 
natural  infection,  429 
occurrence,  429 
symptoms,  429,  430 
treatment,  430 
Lyssa,  382 

M 

Mad  itch,  231 
Madness,  canine,  382 
Mai  de  caderas,  458 
course,  459 
definition,  458 
etiology,  458 
occurrence,  458 
prevention,  459 
prognosis,  459 
symptoms,  458 
treatment,  459 
Mahgnant  edema,  285 
»    head  catarrh  of  ox,  366 
Malleus,  417 
Mange,  259 
of  cattle,  264 

sj'mptoms,  264 
•    treatment,  264 
definition,  259 
etiologv,  259 
follicular,  265 
diagnosis,  265 
etiology,  265 
occurrence,  265 


INDEX 


475 


Mange,  follicular,  prognosis,  265 
of  horse,  260 
forms,  260 
psoroptic,  261 
diagnosis,  261 
prognosis,  261 
treatment,  261 
sarcoptic,  260 
definition,  260 
diagnosis,  260 
prognosis,  260 
sjTnptoms,  26(i 
treatment,  260,  261 
SJ^nbiotic,  261 
diagnosis,  261 
prognosis,  261 
sj'mptoms,  261 
treatment,  261 
occurrence,  259 
of  sheep,  261 
forms,  261 
psoroptic,  262 

diagnosis,  262,  263 
occmTence,  262 
prognosis,  263 
symptoms,  262 
treatment,  263 
sarcoptic,  263 
prognosis,  263 
sj'mptoms,  263 
treatment,  263 
symbiotic,  264 
of  swine,  264 

sjTiiptoms,  264,  265 
treatment,  265 
symbiotic,  264 

treatment,  264 
varieties,  259 
psoroptic,  259,  260 
sarcoptic,  259 
sj-mbiotic,  260 
^Maxillary     and     frontal     sinuses, 
catarrh  of,  26 
definition,  26 
diagnosis,  26 
etiology,  26 
occurrence,  26 
symptoms,  26 
treatment,  26 
Measles,  hog,  197 
Miescher's  tubules,  198 
Meningitis,  236 
acute  spinal,  236 
course,  237 


Meningitis,  acute  spinal,  diagnosis, 
237 
etiology,  236 
occurrence,  236 
symptoms,  236,  237 
treatment,  238 
enzootic  cerebrospinal,  of  horse, 
225 
Meningo-encephalitis,  217 
course,  219 
definition,  217 
diagnosis,  219,  220 
etiology,  217,  218 
infectious,  225 
occurrence,  217 
prognosis,  220 
symptoms,  218,  219 
treatment,  220,  221 
Meningomyehtis,  236 
Milk  fever,  161 
Mold  poisoning,  125 
Muscular  rheumatism,  193 
MyeUtis,  spinal,  238 
course,  239 
definition,  238 
chagnosis,  239,  240 
eliologj',  238 
forms,  238 
diffuse,  239 
disseminated,  239 
transverse,  238,  239 
occurrence,  238 
prognosis,  239 
sjTBptoms,  238 
treatment,  240 
Myocarditis,  76 
definition,  76 
etiology,  76,  77 
sjTnptoms,  77 
treatment,  77 


N 

Nagaxa,  457 
definition,  457 
diagnosis,  457 
etiology,  457 
occurrence,  457 
prevention,  458 
SA'mptoms,  457,  458 

Nasal  catarrh,  17 

Navel  ill,  308 

Necrobacillosis,  272 


476 


INDEX 


Necrosis  of  liver,  150 
definition,  150 
symptoms,  150 
treatment,  150 
Necrotic  stomatitis  of  calves,  367 
Nephritis,  199 

acute  parenchymatous,  199 
course,  200 
definition,  199 
diagnosis,  200 
etiology,  199,  200 
occurrence,  199 
prognosis,  201 
symptoms,  200 
treatment,  201 
chronic  interstitial,  201 
definition,  201 
etiology,  202 
occurrence,  201 
prognosis,  202 
symptoms,  202 
treatment,  202 
purulent,  202 
definition,  202 
etiology,  202,  203 
occurrence,  202 
prognosis,  203 
sj^mptoms,  203 
treatment,  203 
Nervous  palpitation  of  heart,  73 
Nettle  rash,  255 
Nodule  disease,  138 
Nymphomania,  163 
etiology,  163 
symptoms,  163,  164 
treatment,  164 


Obesity,  186 

definition,  186,  187 

treatment,  187 
(Esophagostonia  in  intestines,  138 
Qilstrus  ovis,  24 

life  history,  25 
Omphalophlebitis,  308 
Osteomalacia,  190 
Osteoporosis,  190 

course,  192 

definition,  190 

diagnosis,  192 

etiology,  191 

necropsy,  191 

occurrence,  191 


Osti'oporosis,  prognosis,  192 
symptoms,  191,  192 
treatment,  192 

Oxyuris  curvula,  140 

Ozena,  IS 


Palisade-worms,  136 
Paralysis,  infectious  bulbar,  231 
course,  232 
definition,  231 
diagnosis,  232 
etiology,  231,  232 
occurrence,  231 
prognosis,  232 
symi)toms,  232 
treatment,  232,  233 
of  pharynx,  91 
of  recurrent  nerve,  32 
Paralytic  hemoglobinuria,  179 
Paraplegia,  enzootic,  242 
course,  243 
definition,  242 
diagnosis,  ^43 
etiology,  242 
natural  infection,  242 
occurrence,  242 
prophylaxis,  243 
symptoms,  242,  243 
treatment,  243 
Parasites,  animal,  in  intestines,  133 
varieties,  133 

echinorhynchus  gigas,  140 
diagnosis,  140 
life  history,  140 
prevention,  140 
treatment,  140 
oesophagostoma,  138 
diagnosis,  139 
life  history,  139 
necropsy,  139 
symptoms,  139 
treatment,  139 
varieties,  138 

ocsoi)hagost()ma  cohim- 
bianum  of  Ameri- 
can sheep,  138 
dentatum    of    swine, 

138 
rad  latum,   138 
venulosum   of   ICuro- 
pean  sheep,   138 
oxyuris  curvula,  140 


INDEX 


477 


Parasites,    animal,  varieties,    oxy- 
uris    curvula,    treatment, 
140 
palisade- worms,  136 
prevention,  138 
treatment,  137 
varieties,  136 
round- worms,  135 
prophylaxis,  136 
symptoms,  135,  136 
treatment,  136 
varieties,  135 
in  horses,  135 
in  ox  and  swine,  135 
tapeworms,  133 
diagnosis,  134 
life  cycle,  133 
prevention,  135 
symptoms,  134 
treatment,  135 
varieties,  134 
in  horse,  134 
in  ox,  134 
in  sheep,  134 
thorn-headed  worm,  140 
uncinaria,  141 

life  lustory,  141 
wliip-worms,  141 
in  kidneys,  208 
in  liver,  151 

in  nose  and  sinuses  of  head,  24 
in  peritoneum,  157 
in  pharynx,  93 
in  stomach,  132 
Paratuberculosis,  intestinal,  410 
Parturient  paresis,  161 
course,  162 
definition,  161 
etiology,  161 
occurrence,  161 
prognosis,  162 
sjTnptoms,  161,  162 
treatment,  162,  163 
Pasteurellosis,  295 
neonatorum,  308 
Pectoral  influenza,  319 
Pemphigus,  258 
definition,  258 
etiology,  258 
prognosis,  258 
Pericarditis,  69 
course,  70,  71 
definition,  69 
diagnosis,  71 


Pericarditis,  etiology,  69 
occurrence,  69 
prognosis,  70,  71 
symptoms,  70 
treatment,  71 
Peritoneum,    animal   parasites   in, 
157 
varieties,  157 
in  horse,  157 
in  sheep,  157 
in  swine,  157 
tumors  in,  157 
symptoms,  157 
treatment,  157 
Peritonitis,  152 
course,  154 
definition,  152 
diagnosis,  153,  154 
etiology,  152 
occurrence,  152 
prognosis,  154 
symptoms,  153 
treatment,  154,  155 
Pestis  equorum,  337 
Petecliial  fe\-Er,  322 
Pharyngitis,  89 
course,  91 
definition,  89 
diagnosis,  90,  91 
etiology,  89 
forms,  89,  90 
occurrence,  89 
symptoms,  90 
treatment,  91 
PharjTix,  89 
paralysis  of,  91 
course,  92 
definition,  91 
diagnosis,  92 
etiology,  92 
symptoms,  92 
treatment,  92,  93   • 
parasites  in,  93 
Pica,  187 
Pinlv  ej^e,  313 
Piroplasmoses,  439,  440 
Piroplasmosis,  440 

of  cattle  (Texas  fever),  440 
course,  443 
definition,  440 
diagnosis,  442,  443 
etiology,  440,  441 
necropsy,  442 
occurrence,  440 


478 


INDEX 


Piroplasmosis    of     cattle     (Texas 
fever),    prevention,    443, 
444,  445,  446 
protective  inoculation,  445 
symptoms,  442 
treatment,  443 
of  European  cattle,  446 
definition,  446 
etiology,  447 
occurrence,  446,  447 
prognosis,  448 
prophylaxis,  448 

protective  inoculation,  448 
symptoms,  447 
treatment,  448 
of  horse,  449 
definition,  449 
diagnosis,  450 
etiology,  449 
occurrence,  449 
symptoms,  449,  450 
treatment,  450 
of  sheep,  450 
definition,  450 
etiology,  450 
symptoms,  450 
treatment,  450 
Pleurisy,  319 
Pleuritis,  61 
course,  64 
definition,  61 
diagnosis,  64 
drugs,  65,  66 
etiology,  61,  62 
occurrence,  61 
prognosis,  65 
symptoms,  62,  63 
treatment,  65 
Pleuropneumonia,    contagious,    of 
cattle,  371 
septic,  of  calves,  299 
definition,  299 
etiology,  299 
natural  infection,  299 
necropsy,  299 
occurrence,  299 
prognosis,  300 
symptoms,  299,  300 
treatment,  300 
Pneumonia,  49 
catarrhal,  54 
course,  56 
definition,  64 
diagnosis,  56 


Pneumonia,  catarrhal,  etiology,  54, 
55 
occurrence,  54 
symptoms,  55,  56 
treatment,  56,  57 
croupous,  49 
fibrinous,  49 

complications,  52 
course,  52,  53 
definition,  49 
diagnosis,  51,  52 
drugs,  53,  54 
etiology,  49,  50 
symptoms,  50,  51 
treatment,  53 
foreign  body,  57 
course,  58 
definition,  57 
diagnosis,  58 
etiology,  57 
necropsy,  57 
prognosis,  58 
symptoms,  57,  58 
treatment,  58 
infectious  fibrinous,  of  horse,  319 
complications,  321 
course,  322 
definition,  319 
diagnosis,  321,  322 
etiology,  320 

natural  infection,  320,  321 
necropsy,  321 
occurrence,  319,  320 
prognosis,  322 
symptoms,  321 
treatment,  322 
interstitial,  59 
course,  60 
definition,  59 
diagnosis,  59 
etiology,  59 
prognosis,  60 
symptoms,  59 
treatment,  60 
metastatic,  58 
definition,  58 
etiology,  58 
necropsy,  59 
symptoms,  59 
treatment,  59 
Pneumonitis,  49 
Pneumopericardium,  72 
definition,  72 
etiology,  72 


INDEX 


479 


Pneumopericardium,      occurrence, 

72 
prognosis,  72 
symptoms,  72 
treatment,  72 
Pneumorrhagia,  43 
Pneumothorax,  66 
course,  67 
definition,  66 
diagnosis,  67 
etiology,  66,  67 
prognosis,  67 
symptoms,  67 
treatment,  67 
Podagra,  186 

Poisoning,  cryptogamic,  125 
forage,  125 
mold,  125 
silage,  125 
Pox,  339 
of  cow,  343 

course,  345 

definition,  343 

diagnosis,  344,  345 

etiology,  343 

natural  infection,  343,  344 

occurrence,  343 

prognosis,  345 

sjinptoms,  344 

treatment,  345 

protective  inoculation,  345 
definition,  339 

etiological  relationship,  339,  340 
etiology,  340 
of  horse,  345 

definition,  345 

etiology,  345 

sjTnptoms,  345 
occurrence,  339 
of  sheep,  340 

complications,  342 

course,  343 

definition,  340 

diagnosis,  343 

etiologj',  340 

natural  infection,  340,  341 

occurrence,  340 

prophj'laxis,  343 

symptoms,  341,  342 

treatment,  343 
Pruritus,  257 
definition,  257 
etiologj^  257 
treatment,  258 


Pseudoleukemia,  172 
definition,  172 
occurrence,  172 
prognosis,  173 
symptoms,  173 
treatment,  173 
Pseudorabies,  231 
Pseudotuberculosis  of  sheep,  412 
Psoroptic  mange,  261 
of  horse,  261 
of  sheep,  262 
Puerperal  septicemia,  159 
course,  160 
definition,  159 
diagnosis,  160 
etiology,  159 
occurrence,  159 
prevention,  160 
prognosis,  160 
symptoms,  159,  160 
treatment,  160 
Pulmonary  edema,  41 

gangrene,  44 
Purpura  hemorrhagica,  322 
compHcations,  324,  325 
foreign-body  pneumonia,  325 
gangrene  of  skin,  324 
gastro-enteritis,  325 
septicemia,  325 
course,  325,  326 
definition,  322 
diagnosis,  325 
etiology,  322,  323 
occurrence,  322 
prognosis,  326 
symptoms,  323,  324 
treatment,  326,  327 
medicinal,  327 
Pyelonephritis,  203 
bacterial,  of  cattle,  203 
diagnosis,  204 
prognosis,  204 
symptoms,  204 
calculous,  204 

definition,  204,  205 
occurrence,  205 
S3'mptoms,  205 
treatment,  205 
definition,  203 
'  etiology,  203 

occurrence,  203 
Pyemic  artliritis,  308 
Pyosepticemia  of  sucldings,  308 
course,  311 


480 


INDEX 


Pyosopticemia  of   sucklings,    dofi- 

nition.  'M)H 
diagnosis,  311 
ctioiogv,  308 
•    natural  infection,  308,  309 
extra-uterine,  308 
intra-uterine,  308 
necropsy,  309,  310 

acute,  309 

chronic,  309,  310 

peracute,  309 
occurrence,  308 
prevention,  312,  313 
prognosis,  312 
symptoms,  310,  311 

articular  form,  310 

septicemic  form,  310 

umbilical  form,  310,  311 
treatment,  312 

vaccination,  312 


R 

Rabies,  382 
course,  387 
definition-,  382 
diagnosis,  386,  387 

(iiagnostic  inoculations,  387 
etiology,  382 
natural  infection,  383 
necropsy,  383 
occurrence,  382 
j)rognosis,  387 
jn-ophylaxis,  388 
symptoms,  383,  384,  385,  386 

in  horse,  384 

in  ox,  385,  386 

in  sheep,  380 

in  swine,  386 
treatment,  387,  388 
Rachitis,  189 
definition,  189 
etiology,  189 
necropsy,  189,  190 
occurrence,  189 
jirognosis,  190 
symptoms,  190 
treatment,  190 
Recurrent  nerve,  paralysis  of,  32 
Red  dysentery,  459 
water,  446 

Rhodesian,  448 
Renal  hemorrhage,  206 
Resjjirations,  209 


Respirations,  Biot,  209 

Cheyne-Stokes,  209 
Rheumatism,  194 
articular,  194 
course,  195,  196 
definition,  194 
diagnosis,  195 
etiology,  194,  195 
symjitoms,  195 
treatment,  196 
muscular,  193 
definition,  193 
etiology,  193 
necropsy,  193 
occurrence,  193 
symptoms,  193,  194 
treatment,  194 
Rhinitis,  17 
catarrhal,  17 
acute,  17 
covu'se,  18 
definition,  17 
etiology,  17 
primary,  17 
secondary,  17 
symptoms,  18 
treatment,  IS 
chronic,  IS 
diagnosis,  19 
ctiolog}',  IS 
symptoms,  18,  19 
treatment,  19,  20 
croupous,  20 
course,  20 
definition,  20 
etiology,  20 
occurrence,  20 
symptoms,  20 
treatment,  20 
diphtheritic,  20 
definition,  20 
diagnosis,  21 
etiology,  21 
occurrence,  20 
symptoms,  21 
treatment,  21 
follicular,  21 
definition,  21 
diagnosis,  22 
etiology,  21 
occurrence,  21 
sj'mptoms,  21 
treatment,  22 
infectious,  of  swine,  23 


INDEX 


481 


Rhinitis,      infectious,     of     swine, 
course,  24 
definition,  23 
diagnosis,  24 
natural  infection,  23 
symptoms,  23,  24 
treatment,  24 
Rhodesian  red  water,  448 
Rickets,  1S9 
Rinderpest,  333 
coiu'se,  336 
definition,  333 
diagnosis,  336 

from  foot-and-mouth   disease, 

336 
from  maUgnant  head  catarrh, 
336 
etiology,  333,  334 
natural  infection,  334 
necropsy,  334,  335 
occurrence,  333 
prognosis,  336 
prophylaxis,  336,  337 

protective  inoculation,  336 
sj^mptoms,  335 
treatment,  336 
Ringworm,  265 
Riverbottom  disease,  174 
Roaring,  32 
course,  34 
definition,  32 
cUagnosis,  33 
etiology,  32,  33 
prognosis,  34 
symptoms,  33 
treatment,  34 
Round-worms,  135 
Rupture  of  heart,  80 
of  liver,  150 


Saccharomycosis,  427 
Saint  Vitus'  dance,  247 
Sarcoptic  mite,  259 
Scab,  2.59 
mites,  259 
varieties,  259 
psoroptic,  259 
sarcoptic,  259    - 
symbiotic,  259 
of  sheep,  261 
Scabies,  259 
Scorbutus,  173 


Scours  of  sucklings,  118 
Screw  fly.  270 
1  life  histor}',  270 

treatment,  270 
Scur\'y,  173 

'  Septic  pleuropneumonia  of  calves, 
i     299 

:  Septicemia,  hemorrhagic,  295 
I      puerperal,  159 

!  Sexual    desire,    abnormaUties    in, 
,  163 

!  diminished,  165 

j  etiolog}^  165 

I  treatment,  165 

Sheep  scab,  261 
Sheep-pox,  340 
Shipping  fever,  319 
Silage  poisoning,  125 
Skin  filaria,  270,  27 1_ 
varieties,  270,  271 

filaria  hemorrhagica,  271 
treatment,  271 
irritans,  271 
treatment,  271 
So-called  cohcs  of  horse,  101 
Sore  throat,  89 
Southern  cattle  fever,  440 
Spasmodic  colic,  113 
Spasms  of  the  diaphragm,  247 
Spinal  cord,  240 

compression  of,  240 
course,  241 
definition,  240 
diagnosis,  241 
etiolog}',  240 
occurrence,  240 
prognosis,  241 
sjTnptoms,  241 
treatment,  241 
contusion  of,  234 
inflammation  of  coverings  of, 
236 
of  substance  of,  238 
traumatic  injury  of,  234 
course,  235 
definition,  234 
diagnosis,  235 
etiology,  234 
occurrence,  234 
prognosis,  235 
sj'mptoms,  234,  235 
treatment,  235 
meningitis,  236 
myelitis,  238 


482 


INDEX 


Spinal     paralysis,     infectious,     of 

horse,  242 
Spiroptera,  133 
Sporadic  dysentery,  118 
Sterility,  165 
definition,  165 
etiology,  166 
occurrence,  166 
prognosis,  166 
symptoms,  166 
treatment,  166 
Stomach,  acute  dilatation  of,  103 
and  bowels,  inflammation  of,  120 
animal  parasites  in,  132 
Stomatitis,  83 
catarrhal,  83 
character,  83 
course,  84 
diagnosis,  85 
etiology,  83,  84 
occurrence,  83 
symptoms,  84 
treatment,  85 
contagious,  of  horse,  352 
course,  354 
definition,  352 
diagnosis,  353,  354 
etiology,  352 

natural  infection,  352,  353 
occurrence,  352 
prophylaxis,  354,  355 
symptoms,  353 
treatment,  354 
mycotic,  87 
definition,  87 
diagnosis,  88 
etiology,  87 
occurrence,  87 
prognosis,  88 
symptoms,  87,  88 
treatment,  88 
necrotic,  of  calves,  369 
course,  370 
definition,  369 
diagnosis,  370 
etiology,  369 
natural  infection,  369 
necropsy,  369,  370 
occurrence,  369 
prevention,  371 
prognosis,  371 
symptoms,  370 
treatment,  371 
papulous,  86 


Stomatitis,  papulous,  definition,  86 
diagnosis,  86,  87 
etiology,  86 
prognosis,  87 
symptoms,  86 
treatment,  87 
vesicular,  85 
course,  86 
definition,  85 
diagnosis,  86 
from  foot-and-mouth  disease, 

86 
from  pustular  stomatitis,  86 
etiology,  85 
occurrence,  85 
symptoms,  85,  86 
treatment,  86 
Strangles,  358 
course,  363,  364 
definition,  358 
diagnosis,  363 
etiology,  358 

natural  infection,  358,  359 
necropsy,  359 
occurrence,  358 
prognosis,  363,  364 
symptoms,  360,  361,  362,  363 
types,  360 
irregular,  361 
regular,  360 
treatment,  364,  365,  366 
protective  inoculation,  365 
active  immunity,  366 
passive  immunity,  366 
Strongylus  armatus,  136 
varieties,  136 

sclerostomiun     bidentatum, 
136, 137 
edentatum,  137 
quadridentatum,  137 
treatment,  137,  138 
contort  us,  138 
convolutus,  138 
tetracanthus,  137 
Sunstroke,  213 

treatment,  213 
Surra,  456 
course,  456 
definition,  456 
etiology,  456 
occurrence,  456 
prevention,  457 
prognosis,  456  f 

symptoms,  456 


IXDEX 


483 


Surra,  treatment.  456,  457 
Swamp  fever,  174 
Swine  erysipelas,  292 

fever,  327 
Symbiotic  mites,  260 


Takosis  of  Angora  goats,  303 
eom^e,  304 
definition,  303 
diagnosis,  304 
etiology,  303,  304 
occurrence.  303 
necropsy,  304 
prophylaxis,  305 
sj'mptoms,  304 
treatment,  304,  305 
Tapeworms,  133 
Tetanus,  376 
course,  380 
definition,  376 
diagnosis,  379,  380 
etiolog>%  376 

natural  infection,  376,  377 
necropsy,  377 
occurrence,  376 
prevention,  381,  382 
prognosis,  380 
sjTnptoms,  377,  378,  379 
in  horse,  377 
in  ox,  379 
in  sheep,  379 
in  swine,  379 
treatment,  380,  381 
hygienic,  380,  381 
medicinal,  381 
Texas  fever,  440 
Thorn-headed  worm,  140 
Ticks.  270 
Trichinosis,  196 
definition,  196 

mode  of  infestation,  196,  197 
occurrence,  196 
s^inptoms,  197 
treatment,  197 
Trichorrhexis  nodosa,  258 
definition,  258 
prognosis,  258 
treatment,  258 
Trj-panosomiasis,  451 
Tsets^  disease,  457 
Tuberculosis,  389 


Tuberculosis,  acute  miharj-,  398 
course,  405,  406 
(lefim'tion,  389 
diagnosis,  402,  403,  404,  405 
diagnostic  inoculation,  405 
microscopic  examination,  404 
tubercuhn  reaction,  403,  404 
etiology,  390 
eradication,  407 

palliative  methods,  407,  408 
Bang,  407,  408 
Ostertag,  408 
radical  method,  407 
natural  infection,  390,  391,  392 
modes  of  elimination,  392,  393 

of  infection,  390,  391,  392 
susceptibUitv,  393 
necropsy,  393,^394,  395,  396,  397 
in  ox,  394 

genital  organs,  397 
kidnevs,  397 
hver,  396,  397 
lungs,  394,  395 
lymph  glands,  396 
serous  membranes,  395,  396 
spleen,  397 
udder,  397 
occurrence,  389,  390 
prognosis,  406 
prophylaxis,  406,  407 
protective  inoculation,  40S 

methods  of  bovovaccination 
408,  409 
Heyman,  409 
Ivhmmer,  409 
Koch-Schlitz.  409 
von  Behring,  408,  409 
svmptoms,  398 
'  fever,  398 
in  horse.  402 
in  ox,  398,  399 
bowels.  401 
genital  organs,  401 
larjTix,  400 
lungs.  399 
appetite,  399 
loss  of  flesh,  399,  400 
percussion,  399 
hTnph  glands,  400 
testes,  401 
udder,  400 
uterus,  401 
vagina,  401 
in  swine,  401 


484 


INDEX 


Tuberculosis,  symptoms,  in  swine, 
bones,  402 
bowels,  401,  402 
joints,  402 
lungs,  401 
lymph  glands,  401 
treatment,  406 
Tubules,  ]Miescher's,  198 
Tumors,  brain,  228,  229 
in  heart,  81 
in  kidney,  207 
in  larynx,  34 
in  lung,  (30 
in  peritoneum,  157 
Typhoid  fever,  313 
Tympanites,  97 

Tympany,  chronic  or  habitual,  100 
diagnosis,  100 
etiology,  100 
prognosis,  100 
sj^mptoms,  100 
treatment,  101 
of  guttural  pouch,  27 


Ulceration,  Up-and-leg,  of  sheep, 

272 
Ulcerous  lymphangitis  of  the  horse, 

429 
Uncinariasis,  141 

diagnosis,  141 

natural  infection,  141 

prevention,  141 

symy)toms,  141 

treatment,  141 
Uremia,  205 

definition,  205 

etiology,  205 

occurrence,  205 

symi)toms,  205,  206 

treatment,  206 
Urticaria,  255 

course,  256 


Urticaria,  definition,  255 

etiology,  255 

external  causes,  255 
internal  causes,  255 

symptoms,  255 

treatment,  256 


Vaginitis,   infectious   granular,  of 
cattle,  436 
course,  437 
definition,  436 
diagnosis,  437 
etiology,  436 
natural  infection,  436 
occurrence,  436 
prevention,  438 
symptoms,  436,  437 
treatment,  437,  438 
Variola,  339 
ovina,  340 
Vertigo,  244 
definition,  244 
diagnosis,  244 
etiology,  244 
occurrence,  244 
symptoms,  244 
treatment,  245 
Volvulus,  111 

W 

Warble  fly,  268 

life  history,  268,  269 

prevention,  269 

treatment,  269 
Wool  eating,  188 

definition,  188 

diagnosis,  188 

etiology,  188 

occurrence,  188 

symptoms,  188 
Worm  colic,  113,  114 


